CVE-2026-99056: high-severity vulnerability in Linux
strparser: make sure __strp_recv isn't running before tearing down the parser
Published · Updated
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 7.8epss 0.2%
exploitation probability
0.2%top 90% of all CVEs
observed exploitation
nono source reports it
In the Linux kernel, the following vulnerability has been resolved:
strparser: make sure __strp_recv isn't running before tearing down the parser
The comment above strp_done() claims that if strp is stopped,
strp_recv will no longer be called. That's only true if the caller has
a mechanism (eg locking) to guarantee that strp_recv() calls that
started before strp_stop() have completed by the time we call
strp_done().
This adds a dummy lock_sock/release_sock pair to guarantee that any
in-flight strp_recv() (which runs under either bh_lock_sock or
lock_sock, depending if it's called from ->sk_data_ready or strp_work)
has completed.
Only espintcp can be affected by this race condition, but this patch
makes sure no future user of strp can have the bug.
This could crash on strp->sk ("general mode" of strp), but this mode
has been here for 9 years and has never been used. It'll be gone soon,
no point worrying about it.
Switch the stopped/paused/etc bits to u8's to avoid races between
strp_stop() and strp_pause/unpause().
A reproducer has been published and turns the possible UAF into an
exploit [1].
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Affected products
Linux · LinuxRelated CVEs — Linux
In the same product, most dangerous first.
CVE-2024-53197HIGHALSA: usb-audio: Fix potential out-of-bound accesses for Extigy and Mbox devicesEPSS 4.1%KEVCVE-2026-31431HIGHcrypto: algif_aead - Revert to operating out-of-placeEPSS 3.4%KEVCVE-2024-53104HIGHmedia: uvcvideo: Skip parsing frames of type UVC_VS_UNDEFINED in uvc_parse_formatEPSS 3.4%KEVCVE-2025-39682CRITICALtls: fix handling of zero-length records on the rx_listEPSS 2.9%KEVCVE-2024-36971HIGHnet: fix __dst_negative_advice() raceEPSS 2.7%KEVCVE-2025-39964HIGHcrypto: af_alg - Disallow concurrent writes in af_alg_sendmsgEPSS 1.4%KEV
References
https://git.kernel.org/stable/c/0984ebc631792acf8fff105112ee74a6b8f1efcchttps://git.kernel.org/stable/c/9f3e9fe1b155e9b4572054d8d140586bc3512ecfhttps://git.kernel.org/stable/c/a18dd388045dc7263d99a07db9de4e0f149ca8f1https://git.kernel.org/stable/c/d2b5f637b9b67a79a50d42614d10653c13b4e449https://git.kernel.org/stable/c/eaa3a29004c063d7e9d5ea55636f693f67e6db0f