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Full vulnerability report · 2026
CVE-2026-68451High confidence

s390/zcrypt: Validate length for CCA ECC private key requests

Linux · Linux

7.8HighCVSS 3.1
Recommended action
Within 7 days

High technical severity; prioritise exposed affected systems while verifying vendor guidance.

Patch available
Distribution package intelligence

Ubuntu vendor package status

Canonical’s release and source-package findings are shown separately from local repository availability.

20 package states
Repository candidate not checked

A published vendor fix does not prove that a matching update is enabled and installable on a particular asset. Confirm the local package candidate before scheduling remediation.

Ubuntu releaseSource packageVendor stateFixed versionEvidence
Ubuntu 24.04 LTSnoble · standard archivelinuxAffected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 8 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-awsAffected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 8 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-azureAffected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 8 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-azure-fdeAffected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 8 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-azure-nvidiaAffected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 8 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-gcpAffected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 8 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-gkeAffected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 8 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-gkeopAffected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 8 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-ibmAffected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 8 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-lowlatencyAffected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 8 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-nvidiaAffected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 8 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-nvidia-lowlatencyAffected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 8 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-nvidia-tegraAffected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 8 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-oem-6.11Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 8 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-oracleAffected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 8 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-raspiAffected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 8 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-raspi-realtimeAffected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 8 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-realtimeAffected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 8 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-riscvAffected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 8 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-xilinxAffected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 8 Sept 2026
Direct vendor intelligence

Authoritative vendor CSAF and VEX advisories

Structured product status and remediation from the issuing vendor. Product-state explanations are always visible; large lists can be searched or downloaded.

1 current
CVE-2026-68451 · CSAF 2.0 · revision 3 · status not statedRed Hat Product Securitykernel: s390/zcrypt: Validate length for CCA ECC private key requests
101 known affected

The vendor explicitly identifies these products as affected by this CVE.

  • kernel as a component of Red Hat Enterprise Linux 10
  • kernel-64k as a component of Red Hat Enterprise Linux 10
  • kernel-64k-core as a component of Red Hat Enterprise Linux 10
  • kernel-64k-debug as a component of Red Hat Enterprise Linux 10
  • kernel-64k-debug-core as a component of Red Hat Enterprise Linux 10
  • kernel-64k-debug-devel as a component of Red Hat Enterprise Linux 10
  • kernel-64k-debug-devel-matched as a component of Red Hat Enterprise Linux 10
  • kernel-64k-debug-modules as a component of Red Hat Enterprise Linux 10
  • kernel-64k-debug-modules-core as a component of Red Hat Enterprise Linux 10
  • kernel-64k-debug-modules-extra as a component of Red Hat Enterprise Linux 10
  • kernel-64k-devel as a component of Red Hat Enterprise Linux 10
  • kernel-64k-devel-matched as a component of Red Hat Enterprise Linux 10
Summary
A flaw was found in the Linux kernel's s390 zcrypt module. The `cca_ecc2protkey()` function, responsible for handling Common Cryptographic Architecture (CCA) Elliptic Curve Cryptography (ECC) private key requests, does not properly validate the length of the key token. This allows a local attacker to provide a malformed key token, potentially leading to memory corruption and a denial of service.
Remediation
Affected
Optional official sources

National CERT insights
?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

Select the national-authority views to include. The exact source language is shown on each matched advisory. Your choice is remembered on this device and encoded in the shareable URL.

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current
ENISA EUVD identifier

EUVD-2026-57920

No EUVD known-exploited evidence

In the Linux kernel, the following vulnerability has been resolved: s390/zcrypt: Validate length for CCA ECC private key requests cca_ecc2protkey() derives the copy length for the CPRB parameter block directly from the length field in the key token. Reject the request early if the token length exceeds the available space in the parameter block.

EUVD state
Present in the current official mapping
Known exploitation
Not present in the current ENISA EUVD known-exploited dataset. This is not proof of no exploitation.
ENISA score
7.8 · CVSS 3.1
Advisory evidence
No linked advisory details stored yet
Recommended actionWithin 7 days

High technical severity; prioritise exposed affected systems while verifying vendor guidance.

Patch available
01

What, why and how

In the Linux kernel, the following vulnerability has been resolved: s390/zcrypt: Validate length for CCA ECC private key requests cca_ecc2protkey() derives the copy length for the CPRB parameter block directly from the length field in the key token. Reject the request early if the token length exceeds the available space in the parameter block.

What

In the Linux kernel, the following vulnerability has been resolved: s390/zcrypt: Validate length for CCA ECC private key requests cca_ecc2protkey() derives the copy length for the CPRB parameter block directly from the length field in the key token. Reject the request early if the token length exceeds the available space in the parameter block.

Why

The current structured CVE record identifies a security weakness, but the root cause requires confirmation in the linked vendor material.

How

An attacker operating through local access may attempt exploitation with low privileges. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

What

In the Linux kernel, the following vulnerability has been resolved: s390/zcrypt: Validate length for CCA ECC private key requests cca_ecc2protkey() derives the copy length for the CPRB parameter block directly from the length field in the key token. Reject the request early if the token length exceeds the available space in the parameter block.

Why

The current structured CVE record identifies a security weakness, but the root cause requires confirmation in the linked vendor material.

How

An attacker operating through local access may attempt exploitation with low privileges. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

02

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
No confirmed evidence

No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.

Public PoC / exploit material
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
None recorded

No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.

Likely attack path
local access → vulnerable operation → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Local
Privileges required
Low: a basic authenticated account is required
User interaction
None
Attack complexity
Low: no specialised conditions are recorded
Security boundary
Unchanged: impact remains within the vulnerable component's security authority
Weakness
?CWE means Common Weakness Enumeration.
CWE not yet assigned
CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Common Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.

AVLocalAttack vector: The attacker needs local access to the vulnerable system.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRLowPrivileges required: The attacker needs basic user-level privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CHighConfidentiality impact: A successful attack can cause a major loss.IHighIntegrity impact: A successful attack can cause a major loss.AHighAvailability impact: A successful attack can cause a major loss.
Post-exploitation / living off the land
Stolen credentials, tokens and legitimate administration functions may provide continued access without deploying a large custom toolset.
A

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

ENISA EUVD · EUVD-2026-57920Official EUVD mapping

In the Linux kernel, the following vulnerability has been resolved: s390/zcrypt: Validate length for CCA ECC private key requests cca_ecc2protkey() derives the copy length for the CPRB parameter block directly from the length field in the key token. Reject the request early if the token length exceeds the available space in the parameter block.

Official EUVD record
BSI · German · WID-SEC-W-2026-2832Linux Kernel: Mehrere Schwachstellen

Ein lokaler Angreifer kann mehrere Schwachstellen in Linux Kernel ausnutzen, um einen nicht näher spezifizierten Angriff durchzuführen, darunter möglicherweise die Offenlegung oder Manipulation von Daten oder Denial-of-Service-Zustände.

Official advisory
CERT-FR · French · CERTFR-2026-AVI-1090Multiples vulnérabilités dans le noyau Linux de Debian

d?id=CVE-2026-68254 Référence CVE CVE-2026-68264 https://www.cve.org/CVERecord?id=CVE-2026-68264 Référence CVE CVE-2026-68266 https://www.cve.org/CVERecord?id=CVE-2026-68266 Référence CVE CVE-2026-68267 https://www.cve.org/CVERecord?id=CVE-2026-68267 Référence CVE CVE-2026-68273 https://www.cve.org/CVERecord?id=CVE-2026-68273 Référence CVE CVE-2026-68276 https://www.cve.org/CVERecord?id=CVE-2026-68276 Référence CVE CVE-2026-68322 https://www.cve.org/CVERecord?id=CVE-2026-68322 Référence CVE CVE-2026-68367 https://www.cve.org/CVERecord?id=CVE-2026-68367 Référence CVE CVE-2026-68431 https://www.cve.org/CVERecord?id=CVE-2026-68431 Référence CVE CVE-2026-68451 https://www.cve.org/CVERecord?id=CVE-2026-68451 Référence CVE CVE-2026-68452 https://www.cve.org/CVERecord?id=CVE-2026-68452 Référence CVE CVE-2026-68480 https://www.cve.org/CVERecord?id=CVE-2026-68480 Référence CVE CVE-2026-72111 https://www.cve.org/CVERecord?id=CVE-2026-72111 Référence CVE CVE-2026-74440 https://www.cve.org/CVERecord?id=CVE-2026-74440 Référence CVE CVE-2026-74441 https://www.cve.org/CVERecord?id=CVE-2026-74441 Référence CVE CVE-2026-74442 https://www.cve.org/CVERecord?id=CVE-2026-74442 Référence CVE CVE-2026-74443 https://www.cve.org/CVERecord?id=CVE-2026-74443 Référence CVE CVE-2026-74444 https://www.cve.org/CVERecord?id=

Official advisory
03

Patch and workaround

Operational remediation based on structured source evidence.

Status
?Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.
Patch available
Affected
kernel as a component of Red Hat Enterprise Linux 10; kernel-64k as a component of Red Hat Enterprise Linux 10; kernel-64k-core as a component of Red Hat Enterprise Linux 10; kernel-64k-debug as a component of Red Hat Enterprise Linux 10; kernel-64k-debug-core as a component of Red Hat Enterprise Linux 10; kernel-64k-debug-devel as a component of Red Hat Enterprise Linux 10; kernel-64k-debug-devel-matched as a component of Red Hat Enterprise Linux 10; kernel-64k-debug-modules as a component of Red Hat Enterprise Linux 10; kernel-64k-debug-modules-core as a component of Red Hat Enterprise Linux 10; kernel-64k-debug-modules-extra as a component of Red Hat Enterprise Linux 10; kernel-64k-devel as a component of Red Hat Enterprise Linux 10; kernel-64k-devel-matched as a component of Red Hat Enterprise Linux 10; kernel-64k-modules as a component of Red Hat Enterprise Linux 10; kernel-64k-modules-core as a component of Red Hat Enterprise Linux 10; kernel-64k-modules-extra as a component of Red Hat Enterprise Linux 10; kernel-abi-stablelists as a component of Red Hat Enterprise Linux 10; kernel-core as a component of Red Hat Enterprise Linux 10; kernel-debug as a component of Red Hat Enterprise Linux 10; kernel-debug-core as a component of Red Hat Enterprise Linux 10; kernel-debug-devel as a component of Red Hat Enterprise Linux 10; kernel-debug-devel-matched as a component of Red Hat Enterprise Linux 10; kernel-debug-modules as a component of Red Hat Enterprise Linux 10; kernel-debug-modules-core as a component of Red Hat Enterprise Linux 10; kernel-debug-modules-extra as a component of Red Hat Enterprise Linux 10; kernel-debug-uki-virt as a component of Red Hat Enterprise Linux 10; kernel-devel as a component of Red Hat Enterprise Linux 10; kernel-devel-matched as a component of Red Hat Enterprise Linux 10; kernel-doc as a component of Red Hat Enterprise Linux 10; kernel-modules as a component of Red Hat Enterprise Linux 10; kernel-modules-core as a component of Red Hat Enterprise Linux 10; and 154 more
Fixed
< 5.10; 5.10.265 ≤ 5.10.*; 5.15.216 ≤ 5.15.*; 6.1.183 ≤ 6.1.*; 6.6.151 ≤ 6.6.*; 6.12.103 ≤ 6.12.*; 6.18.44 ≤ 6.18.*; 7.1.8 ≤ 7.1.*
Action
Review the linked authoritative reference and apply the recorded fixed release appropriate to the affected product branch.
Workaround
No verified workaround is recorded. Limit untrusted access and use least privilege until authoritative guidance is available.
04

Evidence and provenance

Published 13 Aug 2026 · Last source change 19 Aug 2026, 16:35 UTC · CWE not yet assigned

CVE recordCVE.org · 5.2
CVSS sourceCNA
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-08-14
European sourceENISA EUVD · EUVD-2026-57920
Product sourceVendor CSAF · Red Hat Product Security
Remediation sourceVendor CSAF · Red Hat Product Security
CWE sourceUnavailable
NVD statusNVD received

Missing structured fields: CWE classification. Missing data is not evidence of low risk; review the primary advisory.

Material change intelligence

What changed after publication

View recent updates →
  1. Vendor guidanceAuthoritative vendor guidance changed from authoritative remediation link to authoritative remediation link.
    Before
    authoritative remediation link
    After
    authoritative remediation link
    CNA
  2. Affected versionsThe structured affected or fixed version information changed.
    Before
    fa6999e326fe7851ecbd572b8cb9be8e930ebf41 < dd25bd9b0f36849808bd7625dcc59dd4c1aeef3e; fa6999e326fe7851ecbd572b8cb9be8e930ebf41 < ecc3b8691c1935f9f3e4eb964ab11e40fdec17f5; fa6999e326fe7851ecbd572b8cb9be8e930ebf41 < 013a4484f061a2b41f052e25c0015203287e63f1; fa6999e326fe7851ecbd572b8cb9be8e930ebf41 < 8fa3e9435a13c335efb63fb4f4e77531a0031159; fa6999e326fe7851ecbd572b8cb9be8e930ebf41 < a9ae0f6dd45c3ccc1d69363f7aea8af179122730; 5.10 · Fixed: < 5.10; 6.6.151 ≤ 6.6.*; 6.12.103 ≤ 6.12.*; 6.18.44 ≤ 6.18.*; 7.1.8 ≤ 7.1.*; 7.2 ≤ *
    After
    fa6999e326fe7851ecbd572b8cb9be8e930ebf41 < 7dc306ff7c4d951582adaae65e0aee9fb4968dbe; fa6999e326fe7851ecbd572b8cb9be8e930ebf41 < 447a37a6bef11bfd3645069e380460b11386e2b9; fa6999e326fe7851ecbd572b8cb9be8e930ebf41 < f0831f13c42c1261d449dcee8a035e1c6cd9fcaa; fa6999e326fe7851ecbd572b8cb9be8e930ebf41 < dd25bd9b0f36849808bd7625dcc59dd4c1aeef3e; fa6999e326fe7851ecbd572b8cb9be8e930ebf41 < ecc3b8691c1935f9f3e4eb964ab11e40fdec17f5; fa6999e326fe7851ecbd572b8cb9be8e930ebf41 < 013a4484f061a2b41f052e25c0015203287e63f1; fa6999e326fe7851ecbd572b8cb9be8e930ebf41 < 8fa3e9435a13c335efb63fb4f4e77531a0031159; fa6999e326fe7851ecbd572b8cb9be8e930ebf41 < a9ae0f6dd45c3ccc1d69363f7aea8af179122730 · Fixed: < 5.10; 5.10.265 ≤ 5.10.*; 5.15.216 ≤ 5.15.*; 6.1.183 ≤ 6.1.*; 6.6.151 ≤ 6.6.*; 6.12.103 ≤ 6.12.*; 6.18.44 ≤ 6.18.*; 7.1.8 ≤ 7.1.*
    CNA
  3. Affected versionsThe structured affected or fixed version information changed.
    Before
    fa6999e326fe7851ecbd572b8cb9be8e930ebf41 < dd25bd9b0f36849808bd7625dcc59dd4c1aeef3e; fa6999e326fe7851ecbd572b8cb9be8e930ebf41 < ecc3b8691c1935f9f3e4eb964ab11e40fdec17f5; fa6999e326fe7851ecbd572b8cb9be8e930ebf41 < 013a4484f061a2b41f052e25c0015203287e63f1; fa6999e326fe7851ecbd572b8cb9be8e930ebf41 < 8fa3e9435a13c335efb63fb4f4e77531a0031159; fa6999e326fe7851ecbd572b8cb9be8e930ebf41 < a9ae0f6dd45c3ccc1d69363f7aea8af179122730; 5.10 · Fixed: < 5.10; 6.6.151 ≤ 6.6.*; 6.12.103 ≤ 6.12.*; 6.18.44 ≤ 6.18.*; 7.1.8 ≤ 7.1.*; 7.2-rc6 ≤ *
    After
    fa6999e326fe7851ecbd572b8cb9be8e930ebf41 < dd25bd9b0f36849808bd7625dcc59dd4c1aeef3e; fa6999e326fe7851ecbd572b8cb9be8e930ebf41 < ecc3b8691c1935f9f3e4eb964ab11e40fdec17f5; fa6999e326fe7851ecbd572b8cb9be8e930ebf41 < 013a4484f061a2b41f052e25c0015203287e63f1; fa6999e326fe7851ecbd572b8cb9be8e930ebf41 < 8fa3e9435a13c335efb63fb4f4e77531a0031159; fa6999e326fe7851ecbd572b8cb9be8e930ebf41 < a9ae0f6dd45c3ccc1d69363f7aea8af179122730; 5.10 · Fixed: < 5.10; 6.6.151 ≤ 6.6.*; 6.12.103 ≤ 6.12.*; 6.18.44 ≤ 6.18.*; 7.1.8 ≤ 7.1.*; 7.2 ≤ *
    CNA
Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
Technical terms and abbreviations used in this report
CVE
Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS
Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS
Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE
Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA
CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP
Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD
National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT
A computer security incident response team that publishes warnings or coordinates incident response.
PoC
Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF
Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL
Living off the land: abuse of legitimate tools or system functions during an attack.
Free version - for non-commercial use only.CVE-2026-68451 · cve.blacktree.nl