CVE-2026-99179watch_queue: Fix note pool publication race in watch_queue_set_size()
- —Not scoredno CVSS score yet
- 0.18%Exploitation in 30 daysEPSS · top 92% 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: watch_queue: Fix note pool publication race in watch_queue_set_size() There is a race between watch_queue_set_size() and post_one_notification(). watch_queue_set_size() publishes wqueue->notes, notes_bitmap, nr_pages and nr_notes with plain stores, and post_one_notification() reads them with plain loads under a different lock, so nothing orders the four stores against the poster's loads: depending on the build, notes can be stored last (gcc 14 on x86-64 does this). Since keyctl_watch_key() lets a watch attach to a queue before it is sized, post_one_notification() can already be running on another CPU at that moment: it reads nr_notes > 0, passes its bounds check, and then reads notes while it is still NULL, dereferencing notes[0]. An unprivileged user triggers this reliably by watching one of its own keys through a notification pipe and racing ioctl(IOC_WATCH_QUEUE_SET_SIZE) on that pipe against keyctl(KEYCTL_SETPERM) on the key from another CPU, triggering: BUG: kernel NULL pointer dereference, address: 0000000000000000 RIP: 0010:post_one_notification.isra.0+0xa2/0x1e0 Call Trace: __post_watch_notification+0x148/0x180 keyctl_setperm_key+0x119/0x130 do_syscall_64+0x108/0x4c0 entry_SYSCALL_64_after_hwframe+0x77/0x7f Kernel panic - not syncing: Fatal exception in interrupt Fix this by publishing nr_notes last with smp_store_release(), and by reading it once with smp_load_acquire() in post_one_notification() before the bitmap and the page array are touched. A poster that observes a non-zero nr_notes then also observes the pool behind it; one that observes zero drops the notification as before.
Timeline
ID reserved
By Linux
- 33 days later
· 33 days later
Published
- 2 days later
· 2 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
No CVSS score yet: neither the CNA, CISA nor NVD has scored this CVE. NVD status: Received.
- EPSS (exploitation in 30 days)
- 0.18% · top 92% of all CVEs (13 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Not scored.
Affected products
- affected c73be61cede5882f9605a852414db559c0ebedfd – < 2137d487b25eefa862be70de489b64f4c679fe1f
- affected c73be61cede5882f9605a852414db559c0ebedfd – < 6aaa6c1a1b61aae332d6e7e0083140b86ea51e14
- affected c73be61cede5882f9605a852414db559c0ebedfd – < 4b20867d80e7e91fb7db531f34035d91591ba405
- affected c73be61cede5882f9605a852414db559c0ebedfd – < da52e5fcb2cae6acdc0d5722ff83499f8232b9d1
- affected c73be61cede5882f9605a852414db559c0ebedfd – < f94c45f83e688e41dfe1b3a589806a0a25567260
- affected c73be61cede5882f9605a852414db559c0ebedfd – < 811fb6d0b07605e8e8d93bde8748be4b3028809a
- affected c73be61cede5882f9605a852414db559c0ebedfd – < 9e73a6754457ffed8399b835552013b9363e51d1
- affected c73be61cede5882f9605a852414db559c0ebedfd – < 5e531d62f1f8834faf7a4eed0d41105cf6570a8f
- affected 5.8
- unaffected < 5.8
- unaffected 5.10.273 – ≤ 5.10.*
- unaffected 5.15.224 – ≤ 5.15.*
- unaffected 6.1.191 – ≤ 6.1.*
- unaffected 6.6.161 – ≤ 6.6.*
- unaffected 6.12.115 – ≤ 6.12.*
- unaffected 6.18.59 – ≤ 6.18.*
- unaffected 7.2.13 – ≤ 7.2.*
- unaffected 7.3 – ≤ *
References
References8
- https://git.kernel.org/stable/c/2137d487b25eefa862be70de489b64f4c679fe1f (opens in a new tab)
- https://git.kernel.org/stable/c/6aaa6c1a1b61aae332d6e7e0083140b86ea51e14 (opens in a new tab)
- https://git.kernel.org/stable/c/4b20867d80e7e91fb7db531f34035d91591ba405 (opens in a new tab)
- https://git.kernel.org/stable/c/da52e5fcb2cae6acdc0d5722ff83499f8232b9d1 (opens in a new tab)
- https://git.kernel.org/stable/c/f94c45f83e688e41dfe1b3a589806a0a25567260 (opens in a new tab)
- https://git.kernel.org/stable/c/811fb6d0b07605e8e8d93bde8748be4b3028809a (opens in a new tab)
- https://git.kernel.org/stable/c/9e73a6754457ffed8399b835552013b9363e51d1 (opens in a new tab)
- https://git.kernel.org/stable/c/5e531d62f1f8834faf7a4eed0d41105cf6570a8f (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-2026-111931 (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)
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[](https://cveledger.app/cve/CVE-2026-99179)Record last updated .