CVE-2026-90149NFSv4/flexfiles: fix NULL dereference for NFSv4.0 data servers
- 7.5HighCVSS base score
- 0.66%Exploitation in 30 daysEPSS · top 48% 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: NFSv4/flexfiles: fix NULL dereference for NFSv4.0 data servers flexfiles accepts NFSv4.0 data servers, but two NFSv4 code paths assume the data server client has a session. Unlike NFSv4.1+, an NFSv4.0 client has no session (clp->cl_session is NULL; it uses clp->cl_slot_tbl), so I/O to a v4.0 flexfiles DS oopses: - nfs4_init_ds_session() dereferences clp->cl_session->session_state while seeding the DS lease. It also only seeds cl_lease_time when NFS4_SESSION_INITING is set; without a session that never happens, so cl_lease_time stays 0 and nfs4_renew_state() busy-loops, requeuing every 5 seconds. Seed the lease whenever there is no session and return before touching session state. - ff_layout_async_handle_error_v4() dereferences clp->cl_session->fc_slot_table on every DS I/O error. Fall back to the v4.0 transport slot table (clp->cl_slot_tbl) when there is no session.
Timeline
ID reserved
By Linux
- 6 days later
· 6 days later
Published
- 43 days later
· 43 days 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 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVDNVD · Received | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.66% · top 48% of all CVEs (13 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.5.
Affected products
- affected a7878ca140084ec267ede48fce64d7e60f6d873e – < e55d7fec8a9290f73032ee34c35dd68532809633
- affected a7878ca140084ec267ede48fce64d7e60f6d873e – < 336b6da10021c69a8f273bbacdf7432fdc89a06f
- affected a7878ca140084ec267ede48fce64d7e60f6d873e – < 5527af72b0100c94287bfec901b6313eeac567ca
- affected a7878ca140084ec267ede48fce64d7e60f6d873e – < 163c16e01f53fc8eb8d0f3484ae6c382265ecbbd
- affected a7878ca140084ec267ede48fce64d7e60f6d873e – < 436a214514e24103159aea455147d58b44a8a585
- affected a7878ca140084ec267ede48fce64d7e60f6d873e – < 2b03ebbf8d5e8f6af4ecd6c65375232dd1ec32cc
- affected 4.12
- unaffected < 4.12
- unaffected 6.1.191 – ≤ 6.1.*
- unaffected 6.6.160 – ≤ 6.6.*
- unaffected 6.12.114 – ≤ 6.12.*
- unaffected 6.18.52 – ≤ 6.18.*
- unaffected 7.2.6 – ≤ 7.2.*
- unaffected 7.3 – ≤ *
References
References6
- https://git.kernel.org/stable/c/e55d7fec8a9290f73032ee34c35dd68532809633 (opens in a new tab)
- https://git.kernel.org/stable/c/336b6da10021c69a8f273bbacdf7432fdc89a06f (opens in a new tab)
- https://git.kernel.org/stable/c/5527af72b0100c94287bfec901b6313eeac567ca (opens in a new tab)
- https://git.kernel.org/stable/c/163c16e01f53fc8eb8d0f3484ae6c382265ecbbd (opens in a new tab)
- https://git.kernel.org/stable/c/436a214514e24103159aea455147d58b44a8a585 (opens in a new tab)
- https://git.kernel.org/stable/c/2b03ebbf8d5e8f6af4ecd6c65375232dd1ec32cc (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-2026-81742 (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-2026-90149)Record last updated .