CVE-2026-118673
KeePassXC: Out-of-bounds write in browser integration response encryption with oversized database responses
KeePassXC is a cross-platform community-driven port of the Windows application KeePass Password Safe. From 2.3.0 until 2.8.0, KeePassXC browser integration encrypts authorized responses in src/browser/BrowserMessageBuilder.cpp using a fixed 1 MiB output vector even though Botan::Sodium::crypto_box_easy() writes the plaintext length plus crypto_box_MACBYTES. A browser-protocol client that can access the per-user IPC endpoint, has a valid database association, and causes an unlocked database to generate and encrypt a sufficiently large authorized response can trigger a sequential out-of-bounds write before any response is delivered. This issue is fixed in version 2.8.0.
Fixes and workarounds
No remediation reported in collected sources.
Missing remediation information is not evidence that no patch exists.
Affected products and versions
| Product | Versions | Authority |
|---|---|---|
| keepassxc keepassxreboot |
>= 2.3.0, < 2.8.0 (affected) | CNA: GitHub_M |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
| Version / score | Vector | Authority |
|---|---|---|
| 4.0 / 4.1 medium |
CVSS:4.0/AV:L/AC:H/AT:P/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N | CNA: GitHub_M |
| 4.0 / 4.1 medium |
CVSS:4.0/AV:L/AC:H/AT:P/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X | NVD: [email protected] |
Exploit evidence
- https://github.com/keepassxreboot/keepassxc/security/advisories/GHSA-3448-gh8j-3227
exploit · ADP: CISA-ADP
References
- https://github.com/keepassxreboot/keepassxc/security/advisories/GHSA-3448-gh8j-3227CNA: GitHub_M · x_refsource_CONFIRM
- https://github.com/keepassxreboot/keepassxc/pull/13679CNA: GitHub_M · x_refsource_MISC
- https://github.com/keepassxreboot/keepassxc/commit/80e68bb4e8b89e383dd96b1bf5de169ca61367aaCNA: GitHub_M · x_refsource_MISC
- https://github.com/keepassxreboot/keepassxc/releases/tag/2.8.0CNA: GitHub_M · x_refsource_MISC
- https://github.com/keepassxreboot/keepassxc/security/advisories/GHSA-3448-gh8j-3227ADP: CISA-ADP · exploit
- https://github.com/keepassxreboot/keepassxc/commit/80e68bb4e8b89e383dd96b1bf5de169ca61367aa[email protected]
- https://github.com/keepassxreboot/keepassxc/pull/13679[email protected]
- https://github.com/keepassxreboot/keepassxc/releases/tag/2.8.0[email protected]
- https://github.com/keepassxreboot/keepassxc/security/advisories/GHSA-3448-gh8j-3227[email protected]
- https://github.com/keepassxreboot/keepassxc/security/advisories/GHSA-3448-gh8j-3227134c704f-9b21-4f2e-91b3-4a467353bcc0
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