CVE-2026-86776

KeePass versions 2.35 through 2.61.1 fail to validate KDBX header field sizes before memory allocation in the ReadHeaderField function. Attackers can craft a malicious KDBX file declaring excessive header field lengths to trigger allocation of gigabytes of memory, causing the application to consume resources and terminate.

CVSS v3 3.3 LOW

3.3^/10

CVSS v3 : LOW

Vector :

Exploitability : 1.8 / Impact : 1.4

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/KSecur1ty/KDBX-Header-Size-Mirage-POC
https://keepass.info/
https://keepass.info/download.html
https://www.vulncheck.com/advisories/keepass-2.35-through-2.61.1-memory-exhaustion-via-kdbx-header-field-size

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-09 10:22

Updated : 2026-09-10 19:58

NVD link : CVE-2026-86776

Mitre link : CVE-2026-86776

CVE.ORG link : CVE-2026-86776

JSON object : View

Products Affected

No product.

CWE

CWE-789

Memory Allocation with Excessive Size Value

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