BlackTreeIndependent security intelligence
← Back to the CVE catalogue
Full vulnerability report · 2026
CVE-2026-68765High confidence

hashcat KeePass KDBX v4 Module Heap Buffer Overflow via Token Field

hashcat · hashcat

5.2MediumCVSS 4.0
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.

Fix not verified
Distribution package intelligence

Ubuntu vendor package status

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

1 package state
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 archivehashcatUnder evaluationCanonical reports that the package might be affected and still needs evaluation or fixing.Not published in this feedCanonical record ↗Source updated 9 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-2026-68765 · CSAF 2.0 · revision 3 · finalRed Hat Product Securityhashcat: hashcat: Heap Buffer Overflow via oversized hash field token
1 known not affected

The vendor explicitly states that these products are not affected by this CVE.

  • All currently supported Red Hat products
Summary
A flaw was found in hashcat. Attackers can exploit a heap buffer overflow vulnerability in the KeePass AESKDF/KDBX v4 module by providing an oversized ninth hash field token. The module processes input up to 600 hexadecimal characters into a fixed 256-byte buffer without proper length validation. This can lead to heap memory corruption or memory access violations, potentially resulting in a denial of service or other unpredictable behavior.
Remediation
No remediation text is recorded.
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-2026-60455

No EUVD known-exploited evidence

hashcat master branch builds after v7.1.2 contain a heap buffer overflow vulnerability in the KeePass AESKDF/KDBX v4 module (module 34301) that allows attackers to corrupt adjacent heap memory by supplying an oversized ninth hash field token. The module accepts up to 600 hex characters for the ninth token field but decodes it into a fixed 256-byte buffer with no length check, allowing a maximal input to write up to 44 bytes past the buffer boundary into adjacent esalt fields and heap chunk metadata, potentially enabling heap corruption or memory access violations.

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
5.2 · CVSS 4.0
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.

Fix not verified
01

What, why and how

hashcat master branch builds after v7.1.2 contain a heap buffer overflow vulnerability in the KeePass AESKDF/KDBX v4 module (module 34301) that allows attackers to corrupt adjacent heap memory by supplying an oversized ninth hash field token. The module accepts up to 600 hex characters for the ninth token field but decodes it into a fixed 256-byte buffer with no length check, allowing a maximal input to write up to 44 bytes past the buffer boundary into adjacent esalt fields and heap chunk metadata, potentially enabling heap corruption or memory access violations.

What

hashcat master branch builds after v7.1.2 contain a heap buffer overflow vulnerability in the KeePass AESKDF/KDBX v4 module (module 34301) that allows attackers to corrupt adjacent heap memory by supplying an oversized ninth hash field token. The module accepts up to 600 hex characters for the ninth token field but decodes it into a fixed 256-byte buffer with no length check, allowing a maximal input to write up to 44 bytes past the buffer boundary into adjacent esalt fields and heap chunk metadata, potentially enabling heap corruption or memory access violations.

Why

A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().

How

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

What

hashcat master branch builds after v7.1.2 contain a heap buffer overflow vulnerability in the KeePass AESKDF/KDBX v4 module (module 34301) that allows attackers to corrupt adjacent heap memory by supplying an oversized ninth hash field token. The module accepts up to 600 hex characters for the ninth token field but decodes it into a fixed 256-byte buffer with no length check, allowing a maximal input to write up to 44 bytes past the buffer boundary into adjacent esalt fields and heap chunk metadata, potentially enabling heap corruption or memory access violations.

Why

A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().

How

An attacker operating through local access may attempt exploitation with elevated 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 → Heap-based Buffer Overflow → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Local
Privileges required
High: elevated access is required
User interaction
Active interaction required
Attack complexity
Low: no specialised conditions are recorded
Security boundary
Not a CVSS 4.0 base metric
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-122 ↗

CWE-122: Heap-based Buffer Overflow. A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:A/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N

Common Vulnerability Scoring System 4.0: 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.ATNoneAttack requirements: No additional deployment or execution condition is required.PRHighPrivileges required: The attacker needs elevated or administrative privileges.UIActiveUser interaction: A user must take a deliberate action for exploitation to succeed.VCNoneVulnerable-system confidentiality: No direct loss is represented by this metric.VILowVulnerable-system integrity: A successful attack can cause a limited loss.VAHighVulnerable-system availability: A successful attack can cause a major loss.SCNoneSubsequent-system confidentiality: No direct loss is represented by this metric.SINoneSubsequent-system integrity: No direct loss is represented by this metric.SANoneSubsequent-system availability: No direct loss is represented by this metric.
Post-exploitation / living off the land
Stolen credentials, tokens and legitimate administration functions may provide continued access without deploying a large custom toolset.
CWE-122
A

Official authority intelligence

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

ENISA EUVD · EUVD-2026-60455Official EUVD mapping

hashcat master branch builds after v7.1.2 contain a heap buffer overflow vulnerability in the KeePass AESKDF/KDBX v4 module (module 34301) that allows attackers to corrupt adjacent heap memory by supplying an oversized ninth hash field token. The module accepts up to 600 hex characters for the ninth token field but decodes it into a fixed 256-byte buffer with no length check, allowing a maximal input to write up to 44 bytes past the buffer boundary into adjacent esalt fields and heap chunk metadata, potentially enabling heap corruption or memory access violations.

Official EUVD record
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.
Fix not verified
Affected
ef52453de9523f6a010652847b61cb340ed5daa5 < 6f374c4ff7d5dc951530fbbbcf6b45e3c169b100
Fixed
No fixed version is explicitly recorded in the structured CVE data.
Action
No verified patch reference is present in the current structured sources. Check the vendor advisory before making a change.
Workaround
No verified workaround is recorded. Limit untrusted access and use least privilege until authoritative guidance is available.
04

Evidence and provenance

Published 17 Aug 2026 · Last source change 21 Aug 2026, 11:20 UTC · CWE-122 · Heap-based Buffer Overflow

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 2026-08-23
European sourceENISA EUVD · EUVD-2026-60455
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceCNA
NVD statusNVD received

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
    ef52453 < 6f374c4 · Fixed: No fixed version is explicitly recorded in the structured CVE data.
    After
    ef52453de9523f6a010652847b61cb340ed5daa5 < 6f374c4ff7d5dc951530fbbbcf6b45e3c169b100 · Fixed: No fixed version is explicitly recorded in the structured CVE data.
    CNA ↗
  2. Affected versionsThe structured affected or fixed version information changed.
    Before
    7.1.2 < 6f374c4 · Fixed: No fixed version is explicitly recorded in the structured CVE data.
    After
    ef52453 < 6f374c4 · Fixed: No fixed version is explicitly recorded in the structured CVE data.
    CNA ↗
  3. Catalogue recordCVE added to the BlackTree catalogue.
    CNA ↗
Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
CVE published
ENISA EUVD · EUVD-2026-60455↗Vendor CSAF · Red Hat Product Security↗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-2026-68765 · cve.blacktree.nl