Vulnerability · Published Sep 9, 2026 · Assigned by VulnCheck
CVE-2026-86776KeePass 2.35 through 2.61.1 Memory Exhaustion via KDBX Header Field Size
Low 3.3
In plain English
A low-severity security flaw in KeePass from KeePass. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 6% of all known vulnerabilities).
Severity (CVSS 3.1)3.3Low
Exploit odds (30 days)0.2%top 93.9% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known
Official description
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 packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | keepass2 | no fix listed | DEBIAN-CVE-2026-86776 |
| Debian:13 | keepass2 | no fix listed | DEBIAN-CVE-2026-86776 |
| Debian:14 | keepass2 | no fix listed | DEBIAN-CVE-2026-86776 |
| Ubuntu:22.04:LTS | keepass2 | no fix listed | UBUNTU-CVE-2026-86776 |
| Ubuntu:24.04:LTS | keepass2 | no fix listed | UBUNTU-CVE-2026-86776 |
| Ubuntu:26.04:LTS | keepass2 | no fix listed | UBUNTU-CVE-2026-86776 |
| Ubuntu:26.10 | keepass2 | no fix listed | UBUNTU-CVE-2026-86776 |
Affected products (as reported)
Weakness: CWE-789 · Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L
References
- Reporter write-up and proof of concept exploit, technical-description
- https://keepass.info/ product
- KeePass 2.61.1 downloads (including source) product
- VulnCheck Advisory: KeePass 2.35 through 2.61.1 Memory Exhaustion via KDBX Header Field Size third-party-advisory