CVE-2026-89975 nvme-fabrics: fix DHCHAP secret leak on parse failure
A local attacker can trigger a memory leak of sensitive DHCHAP secrets in the Linux kernel NVMe fabrics driver, potentially causing denial of service or secret exposure.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-89975?
CVE-2026-89975 is a memory corruption vulnerability in Linux, published on 16 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
nvme-fabrics: fix DHCHAP secret leak on parse failure
nvmf_parse_options() duplicates dhchap_secret and dhchap_ctrl_secret with match_strdup() before validating the DHHC-1: representation.
If validation fails, the parser returns -EINVAL before the temporary string in p is assigned to opts->dhchap_secret or opts->dhchap_ctrl_secret. nvmf_create_ctrl() subsequently frees opts, but nvmf_free_options() cannot release the unassigned temporary string. Each rejected option therefore leaks one allocation.
This is easy to miss because valid secrets transfer ownership to opts and are freed normally, while the malformed-secret path still returns the expected -EINVAL to userspace.
With CONFIG_NVME_HOST_AUTH enabled, the leak is reachable before the required-option checks and transport lookup. No NVMe-oF target or working transport connection is required; for example, repeatedly writing
dhchap_secret=BAD
or
dhchap_ctrl_secret=BAD
to /dev/nvme-fabrics deterministically takes the leaking parse path.
Free the temporary string before leaving both validation error paths. Use kfree_sensitive() because the copied option may contain secret material even when its representation is rejected, matching the sensitive cleanup used for stored DHCHAP secrets.
Which versions are affected by CVE-2026-89975?
How do I fix CVE-2026-89975?
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-2026-89975 being exploited?
There is no known exploitation of CVE-2026-89975 in the wild and no public exploit code.
Sources
Also known as AZL-101645, BELL-CVE-2026-89975, DEBIAN-CVE-2026-89975, GHSA-9hxp-3v8h-pjp2, UBUNTU-CVE-2026-89975.