CVE-2026-86776 KeePass 2.35 through 2.61.1 Memory Exhaustion via KDBX Header Field Size
Attackers can cause denial of service in KeePass by crafting malicious KDBX files with excessive header field sizes, leading to memory exhaustion.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-86776?
CVE-2026-86776 is a medium-severity denial of service vulnerability in KeePass, published on 9 Sep 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
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.
Weakness: CWE-789
Which versions are affected by CVE-2026-86776?
How do I fix CVE-2026-86776?
No fix has been published for CVE-2026-86776 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-86776 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-86776 exists.
Sources
Also known as DEBIAN-CVE-2026-86776, GHSA-5r36-v86r-vm5x, UBUNTU-CVE-2026-86776.