CVE-2026-72130 nvmet-auth: reject short AUTH_RECEIVE buffers
Remote NVMe-oF initiators can trigger heap out-of-bounds writes in Linux kernel NVMe targets when DH-HMAC-CHAP authentication is enabled.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-72130?
CVE-2026-72130 is a critical memory corruption vulnerability in Linux, published on 15 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
nvmet-auth: reject short AUTH_RECEIVE buffers
nvmet_execute_auth_receive() trusts the AUTH_RECEIVE allocation length after checking only that it is nonzero and matches the transfer length. In the SUCCESS1 and FAILURE1/default states, that lets a remote NVMe-oF initiator reach the fixed-size DH-HMAC-CHAP response builders with a kmalloc() buffer shorter than the response, so nvmet_auth_success1() and nvmet_auth_failure1() write past the allocation; both only WARN_ON the short length and then format the message anyway.
Impact: A remote NVMe-oF initiator with access to an auth-enabled target can trigger a 16-byte heap out-of-bounds write via a one-byte AUTH_RECEIVE allocation length.
Compute the minimum response length for the current DH-HMAC-CHAP step in nvmet_auth_receive_data_len() and report a zero data length when the host-supplied allocation length is shorter, so the existing zero-length check in nvmet_execute_auth_receive() rejects the command before any builder runs. The SUCCESS1 minimum is sizeof(struct nvmf_auth_dhchap_success1_data) plus the HMAC hash length, because the response hash is written into the rval[] flexible-array tail, so the minimum is state dependent rather than a flat sizeof. CHALLENGE keeps its existing variable-length guard in nvmet_auth_challenge().
This is reachable only when in-band DH-HMAC-CHAP authentication is configured on the target.
Which versions are affected by CVE-2026-72130?
How do I fix CVE-2026-72130?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-72130 being exploited?
There is no known exploitation of CVE-2026-72130 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-72130, DEBIAN-CVE-2026-72130, GHSA-m9xx-q2g4-96mr, UBUNTU-CVE-2026-72130.