CVE-2026-87732 Other in mirage-crypto
Attackers can read decrypted plaintext from a buffer even when authentication tags are forged, bypassing integrity checks in the mirage-crypto library.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-87732?
CVE-2026-87732 is a medium-severity vulnerability in OCaml mirage-crypto, published on 9 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
An issue was discovered in the mirage-crypto package before 2.2.0 for OCaml. The AES.GCM.authenticate_decrypt_into and Chacha20.authenticate_decrypt_into functions write the decrypted plaintext into a caller-provided buffer and only then compares the tag. On a forged tag, the functions returns false, but the destination buffer already holds the full plaintext.
Weakness: CWE-347
Which versions are affected by CVE-2026-87732?
How do I fix CVE-2026-87732?
Upgrade to a fixed version.
Is CVE-2026-87732 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-87732 exists.
Sources
Also known as DEBIAN-CVE-2026-87732, GHSA-vqxm-cgmv-2pcr, OSEC-2026-12, UBUNTU-CVE-2026-87732.