CVE-2026-64535nvmet-tcp: Fix potential UAF when ddgst mismatch
- 9.8CriticalCVSS base score
- 0.55%Exploitation in 30 daysEPSS · top 54% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
In the Linux kernel, the following vulnerability has been resolved: nvmet-tcp: Fix potential UAF when ddgst mismatch Shivam Kumar found via vulnerability testing: When data digest is enabled on an NVMe/TCP connection and a digest mismatch occurs on a non-final H2C_DATA PDU during an R2T-based data transfer, the digest error handler in nvmet_tcp_try_recv_ddgst() calls nvmet_req_uninit() — which performs percpu_ref_put() on the submission queue — but does NOT mark the command as completed. It does not set cqe->status, does not modify rbytes_done, and does not clear any flag. When the subsequent fatal error triggers queue teardown, nvmet_tcp_uninit_data_in_cmds() iterates all commands, checks nvmet_tcp_need_data_in() for each one, and finds that the already-uninited command still appears to need data (because rbytes_done < transfer_len and cqe->status == 0). It therefore calls nvmet_req_uninit() a second time on the same command — a double percpu_ref_put against a single percpu_ref_get.
Timeline
ID reserved
By Linux
- 8 days later
· 8 days later
Published
- 3 months later
· 3 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| LinuxCNA (assigner) | 3.1 | Critical9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Awaiting Analysis | 3.1 | Critical9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.55% · top 54% of all CVEs (15 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: yes · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 9.8.
Affected products
- affected 91edfca6f8b364d60cde3ddefaf7d03ddf35774b – < dfb902462bca478f050224ec7a7195aafa7643b1
- affected fda871c0ba5d2eed2cd1c881573168129da70058 – < 7e558308eba14c8136cb1e615f0c850f76d1fc0a
- affected fda871c0ba5d2eed2cd1c881573168129da70058 – < 96fe2513df590e74b04253a45089cae75569570e
- affected fda871c0ba5d2eed2cd1c881573168129da70058 – < e091ff83d962f9ed00d9bd70443676de9fe98bdc
- affected fda871c0ba5d2eed2cd1c881573168129da70058 – < 6f9442983a3e4227afd1c83a5251ddbca585ea21
- affected fda871c0ba5d2eed2cd1c881573168129da70058 – < 088ee46c18d99baef453afd74181dd40ade044ad
- affected fda871c0ba5d2eed2cd1c881573168129da70058 – < dbbd07d0a7020b80f6a7028e561908f7b83b3d5a
- affected 4b17476d809273617d3317fa0d4ae78aa488d760
- affected 5.10.20 – < 5.10.265
- affected 5.11.3 – < 5.12
- affected 5.12
- unaffected < 5.12
- unaffected 5.10.265 – ≤ 5.10.*
- unaffected 5.15.216 – ≤ 5.15.*
- unaffected 6.1.178 – ≤ 6.1.*
- unaffected 6.6.145 – ≤ 6.6.*
- unaffected 6.12.97 – ≤ 6.12.*
- unaffected 6.18.40 – ≤ 6.18.*
- unaffected 7.1 – ≤ *
References
References7
- https://git.kernel.org/stable/c/dfb902462bca478f050224ec7a7195aafa7643b1 (opens in a new tab)
- https://git.kernel.org/stable/c/7e558308eba14c8136cb1e615f0c850f76d1fc0a (opens in a new tab)
- https://git.kernel.org/stable/c/96fe2513df590e74b04253a45089cae75569570e (opens in a new tab)
- https://git.kernel.org/stable/c/e091ff83d962f9ed00d9bd70443676de9fe98bdc (opens in a new tab)
- https://git.kernel.org/stable/c/6f9442983a3e4227afd1c83a5251ddbca585ea21 (opens in a new tab)
- https://git.kernel.org/stable/c/088ee46c18d99baef453afd74181dd40ade044ad (opens in a new tab)
- https://git.kernel.org/stable/c/dbbd07d0a7020b80f6a7028e561908f7b83b3d5a (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-49113 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-64535)Record last updated .