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Full vulnerability report · 2026
CVE-2026-26081High confidence

HAProxy Community Edition 3.0 through 3.3 before 3.3.3 lacks a length check for the NEW_TOKEN format

HAProxy · HAProxy

4.8MediumCVSS 3.1
Recommended action
Scheduled

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.

Patch available
R
Operational reassessment

Published severity in operational context

Open reassessment dashboard →
Published severityMediumOperational priority:Medium, unchanged from published severity.unchanged

Evidence used

  • No CISA KEV confirmation is currently recorded.
  • The selected CVSS metric records a network-reachable, unauthenticated path with no user interaction.
  • EPSS is 0.48% for the current model date.

Compensating controls

  • Validate the affected product branch and deploy the verified fixed release.
  • Restrict the affected network interface to trusted sources where business-safe.
  • Monitor vendor guidance and exploitation sources for a material change.

Verification

  1. Confirm that the asset runs HAProxy HAProxy and falls inside the recorded affected range.
  2. Verify the installed build against the product-specific fixed version after deployment.
  3. Validate exposure, authentication requirements and compensating controls in the actual environment.
  4. Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Mitigation target: As exposure requiresRemediation target: Within 365 days

This automated reassessment organises public evidence. It does not know asset exposure, business impact or control effectiveness and does not replace CVSS or a human risk decision.

Distribution package intelligence

Release-specific package status

Debian findings are scoped to the named distribution, release and source package. An absent finding does not mean a package is unaffected.

4 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.

Distribution releaseSource packageVendor stateFixed versionEvidence
Debian trixietrixie · sourcehaproxyVendor fix publishedDebian records a fixed source-package version for this release.3.0.11-1+deb13u2Debian Security Tracker ↗Source updated 6 Oct 2026
Debian bookwormbookworm · sourcehaproxyNot affectedDebian marks this release not affected (fixed-version marker 0).Not published in this feedDebian Security Tracker ↗Source updated 6 Oct 2026
Debian forkyforky · sourcehaproxyVendor fix publishedDebian records a fixed source-package version for this release.3.2.11-2Debian Security Tracker ↗Source updated 6 Oct 2026
Debian sidsid · sourcehaproxyVendor fix publishedDebian records a fixed source-package version for this release.3.2.11-2Debian Security Tracker ↗Source updated 6 Oct 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-2026-26081 · CSAF 2.0 · revision 3 · finalRed Hat Product Securityhaproxy: HAProxy: Data integrity and availability vulnerability in NEW_TOKEN format
23 known affected

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

  • haproxy.src as a component of Red Hat Ceph Storage 5
  • haproxy22 as a component of Red Hat Ceph Storage 5
  • rhceph/rhceph-haproxy-rhel8 as a component of Red Hat Ceph Storage 5
  • rhceph/rhceph-haproxy-rhel9 as a component of Red Hat Ceph Storage 6
  • rhceph/rhceph-haproxy-rhel9 as a component of Red Hat Ceph Storage 7
  • rhceph/rhceph-haproxy-rhel9 as a component of Red Hat Ceph Storage 8
  • rhceph-ci/haproxy as a component of Red Hat Ceph Storage 9
  • rhceph/rhceph-haproxy-rhel10 as a component of Red Hat Ceph Storage 9
  • rhceph/rhceph-haproxy-rhel9 as a component of Red Hat Ceph Storage 9
  • haproxy as a component of Red Hat Enterprise Linux 10
  • haproxy.src as a component of Red Hat Enterprise Linux 10
  • haproxy as a component of Red Hat Enterprise Linux 7
Summary
A flaw was found in HAProxy. This vulnerability, stemming from a missing length check in the NEW_TOKEN format, could allow a remote attacker to cause a low impact on data integrity and availability. This means an attacker might be able to subtly alter data or temporarily disrupt the service.
Remediation
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://images.redhat.com/
Optional official sources

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

Choose official national sources for this report. Each advisory shows its original language. Your selection is remembered on this device and included in shared links.

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-2026-45989

No EUVD known-exploited evidence

ENISA has published the identifier mapping but no EUVD description has been stored yet.

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
Not supplied in the stored EUVD record
Advisory evidence
No linked advisory details stored yet
Recommended actionScheduled

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.

Patch available
01

What, why and how

HAProxy Community Edition 3.0 through 3.3 before 3.3.3 lacks a length check for the NEW_TOKEN format. HAProxy Enterprise and ALOHA are also affected.

What

HAProxy Community Edition 3.0 through 3.3 before 3.3.3 lacks a length check for the NEW_TOKEN format. HAProxy Enterprise and ALOHA are also affected.

Why

The product parses a formatted message or structure, but it does not handle or incorrectly handles a length field that is inconsistent with the actual length of the associated data.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

What

HAProxy Community Edition 3.0 through 3.3 before 3.3.3 lacks a length check for the NEW_TOKEN format. HAProxy Enterprise and ALOHA are also affected.

Why

The product parses a formatted message or structure, but it does not handle or incorrectly handles a length field that is inconsistent with the actual length of the associated data.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. 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
a network path → Improper Handling of Length Parameter Inconsistency → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Network
Privileges required
None: unauthenticated exploitation is possible
User interaction
None
Attack complexity
High: exploitation depends on specific conditions
Security boundary
Unchanged: impact remains within the vulnerable component's security authority
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-130 ↗

CWE-130: Improper Handling of Length Parameter Inconsistency. The product parses a formatted message or structure, but it does not handle or incorrectly handles a length field that is inconsistent with the actual length of the associated data.

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:L

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

AVNetworkAttack vector: The vulnerable component can be reached over a network.ACHighAttack complexity: Successful exploitation depends on specific conditions outside the attacker's direct control.PRNonePrivileges required: The attacker does not need an account or existing privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CNoneConfidentiality impact: No direct loss is represented by this metric.ILowIntegrity impact: A successful attack can cause a limited loss.ALowAvailability impact: A successful attack can cause a limited loss.
Post-exploitation / living off the land
Stolen credentials, tokens and legitimate administration functions may provide continued access without deploying a large custom toolset.
NetworkUnauthenticatedCWE-130
A

Official authority intelligence

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

BSI · German · WID-SEC-2026-0410HAProxy Enterprise, Community und ALOHA (QUIC): Mehrere Schwachstellen ermöglichen Denial of Service

Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in HAProxy Enterprise, Community und ALOHA ausnutzen, um einen Denial of Service Angriff durchzuführen.

Official advisory ↗
Cyber Security Agency of Singapore · English · CSA-SB-20260722Security Bulletin 22 Jul 2026

The Cyber Security Agency of Singapore included this CVE in its official Security Bulletin 22 Jul 2026, published on 22 July 2026. Open the linked bulletin for the product, severity and reference information published in that issue.

Official advisory ↗
CERT-FR · French · CERTFR-2026-AVI-0163Multiples vulnérabilités dans HAProxy

De multiples vulnérabilités ont été découvertes dans HAProxy. Elles permettent à un attaquant de provoquer un déni de service à distance.

Official advisory ↗
JVN iPedia · Japanese · JVNDB-2026-030186HAProxy TechnologiesのAloha等の複数製品におけるレングスパラメーターの不整合による処理に関する脆弱性

HAProxy Community Edition 3.0から3.3までのバージョン（3.3.3未満）には、NEW_TOKEN形式の長さチェックが欠如しています。HAProxy EnterpriseおよびALOHAも同様に影響を受けます。

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
Fixed
Action
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://images.redhat.com/
Workaround
No verified workaround is recorded. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
04

Evidence and provenance

Published 20 Jul 2026 · Last source change 20 Jul 2026, 18:18 UTC · CWE-130 · Improper Handling of Length Parameter Inconsistency

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-2026-45989
Product sourceVendor CSAF · Red Hat Product Security
Remediation sourceVendor CSAF · Red Hat Product Security
CWE sourceCNA
NVD statusNVD enriched

Core structured fields are present and their contributing authorities are shown above.

Material change intelligence

What changed after publication

View recent updates ↗
  1. Affected versionsThe structured affected or fixed version information changed.
    Before
    3.0 < 3.0.12; 3.1 < 3.1.14; 3.2 < 3.2.12; 3.3 < 3.3.3 · Fixed: An authoritative update reference is available, but the fixed version is not recorded in the structured CVE fields. Check the linked vendor advisory for the applicable release.
    After
    3.0 < 3.0.12; 3.1 < 3.1.14; 3.2 < 3.2.12; 3.3 < 3.3.3 · Fixed: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://images.redhat.com/
    Red Hat Product Security ↗
  2. Affected versionsThe structured affected or fixed version information changed.
    Before
    Fixed: haproxy-main@aarch64 as a component of Red Hat Hardened Images; haproxy-main@src as a component of Red Hat Hardened Images; haproxy-main@x86_64 as a component of Red Hat Hardened Images
    After
    haproxy.src as a component of Red Hat Ceph Storage 5; haproxy22 as a component of Red Hat Ceph Storage 5; rhceph/rhceph-haproxy-rhel8 as a component of Red Hat Ceph Storage 5; rhceph/rhceph-haproxy-rhel9 as a component of Red Hat Ceph Storage 6; rhceph/rhceph-haproxy-rhel9 as a component of Red Hat Ceph Storage 7; rhceph/rhceph-haproxy-rhel9 as a component of Red Hat Ceph Storage 8; rhceph-ci/haproxy as a component of Red Hat Ceph Storage 9; rhceph/rhceph-haproxy-rhel10 as a component of Red Hat Ceph Storage 9; rhceph/rhceph-haproxy-rhel9 as a component of Red Hat Ceph Storage 9; haproxy as a component of Red Hat Enterprise Linux 10; haproxy.src as a component of Red Hat Enterprise Linux 10; haproxy as a component of Red Hat Enterprise Linux 7; haproxy.src as a component of Red Hat Enterprise Linux 7; haproxy as a component of Red Hat Enterprise Linux 8; haproxy.src as a component of Red Hat Enterprise Linux 8; haproxy as a component of Red Hat Enterprise Linux 9; haproxy.src as a component of Red Hat Enterprise Linux 9; haproxy.src as a component of Red Hat OpenShift Container Platform 4; haproxy18 as a component of Red Hat OpenShift Container Platform 4; haproxy20 as a component of Red Hat OpenShift Container Platform 4; haproxy22 as a component of Red Hat OpenShift Container Platform 4; haproxy26 as a component of Red Hat OpenShift Container Platform 4; haproxy28 as a component of Red Hat OpenShift Container Platform 4 · Fixed: haproxy-main@aarch64 as a component of Red Hat Hardened Images; haproxy-main@src as a component of Red Hat Hardened Images; haproxy-main@x86_64 as a component of Red Hat Hardened Images
    Red Hat Product Security ↗
  3. Vendor guidanceAuthoritative vendor guidance changed: added patch: git.haproxy.org?p=haproxy-3.2.git;a=commit;h=4765277f4f915baac2d57db63538ff0a59966deb; added remediation: git.haproxy.org?p=haproxy-3.2.git;a=commit;h=4765277f4f915baac2d57db63538ff0a59966deb.
    Before
    no authoritative guidance recorded
    After
    patch: git.haproxy.org?p=haproxy-3.2.git;a=commit;h=4765277f4f915baac2d57db63538ff0a59966deb · remediation: git.haproxy.org?p=haproxy-3.2.git;a=commit;h=4765277f4f915baac2d57db63538ff0a59966deb
    cve@mitre.org ↗
  4. Affected versionsThe structured affected or fixed version information changed.
    Before
    3.0 < 3.0.12; 3.1 < 3.1.14; 3.2 < 3.2.12; 3.3 < 3.3.3 · Fixed: No fixed version is explicitly recorded in the structured CVE data.
    After
    3.0 < 3.0.12; 3.1 < 3.1.14; 3.2 < 3.2.12; 3.3 < 3.3.3 · Fixed: An authoritative update reference is available, but the fixed version is not recorded in the structured CVE fields. Check the linked vendor advisory for the applicable release.
    CNA ↗
  5. Remediation statusRemediation status changed from Awaiting fix to Patch available.
    Before
    Awaiting fix
    After
    Patch available
    cve@mitre.org ↗
Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
CVE published
Fixed release or patch reference recorded
Fixed release recorded from official guidance
ENISA EUVD · EUVD-2026-45989↗Red Hat Product Security security advisory↗Patch or update reference↗CVE authority or vendor reference↗Official CVE record (CNA and ADP data)↗NVD record↗
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-2026-26081 · cve.blacktree.nl