CVE-2026-86776: KeePass 2.35 through 2.61.1 Memory Exhaustion via KDBX Header Field Size

Published Sep 9, 2026
·
Updated

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.

Affected Software

1 affected component
KeePass KeePass>=2.35<=2.61.1

Event History

Sep 9, 2026
CVE Published
via MITRE·10:07 AM
Data Sourced
via MITRE·10:07 AM
DescriptionSeverityWeakness

Frequently Asked Questions

1

Who is exposed to this issue?

Users running KeePass 2.35 through 2.61.1 are exposed when they open a maliciously crafted KDBX file. The attack requires user interaction, as indicated by the UI:R vector.

2

What does an attacker need to exploit it?

An attacker needs to provide a KDBX file with excessively large declared header field lengths and induce the target to open it in the affected KeePass versions. No privileges are required, and the attack is local.

3

What is the likely impact of successful exploitation?

KeePass may allocate gigabytes of memory while processing the malformed KDBX header, exhausting system resources and terminating the application. The provided severity vector indicates availability impact only, with no confidentiality or integrity impact.

Contact

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Fortitude Valley,
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info@secalerts.co
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