Vulnerability in Keepass
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 3.3 (Low). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L.
EPSS exploit prediction
EPSS: 0.002 (5.7th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 6th percentile — 5.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: 0.000
Affected products
Weakness classification (CWE)
References
- github.com/KSecur1ty/KDBX-Header-Size-Mirage-POC (technical-description, exploit)
- keepass.info/ (product)
- keepass.info/download.html (product)
- www.vulncheck.com/advisories/keepass-2.35-through-2.61.1-memory-exhaustion-via-… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-86776?
- CVE-2026-86776 is a low-severity vulnerability in Keepass, classified under CWE-789. CVSS score: 3.3/10. Published 2026-09-09.
- How severe is CVE-2026-86776?
- Low severity. CVSS v3 base score is 3.3 out of 10.