CVE-2026-68143

net: slip: serialize receive against buffer reallocation

State: Published
Severity: 7.8 High
Published: Aug 10, 2026
Updated: Oct 19, 2026
Reserved: Jul 30, 2026

Description

In the Linux kernel, the following vulnerability has been resolved:

net: slip: serialize receive against buffer reallocation

sl_realloc_bufs() replaces rbuff and updates buffsize while holding sl->lock. slip_receive_buf() reads those fields and writes through rbuff without holding the lock.

An MTU change can therefore race with receive processing. An MTU shrink can expose the new smaller rbuff with the old larger bound, causing an out-of-bounds write. A receive callback which already loaded the old rbuff can instead continue writing after that buffer has been freed.

Serialize receive processing with sl_realloc_bufs() by holding sl->lock while consuming each receive batch.

Scores

CVSS	Score	Vector	Source
3.1	7.8 High	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H	Linux

Weaknesses

CWE-362 Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

Affected Products

Product	Versions
LinuxLinux	1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to before 8180daf2b66155f84ec4f9e3f95488c8a3421716Affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to before 189a550eb7e1dc10018718ddfc46d003ffe58653Affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to before 1be09d175b627fad7f6bec7ad27b8a4a99863912Affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to before eb3836eab47487823f362e6985e170a1e15f20fdAffected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to before 44401f7dd9940ced7098930ef64f5a332f279fc2Affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to before 5d07b178bef511d69558cfc89fe1129258dc39f8Affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to before 0e37bbd6d617eb52bace49390e99eaedc1af73ceAffected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to before ee7f9bb9320add61f7b367d7e6cd55e3a3a4d65dAffected
LinuxLinux	2.6.12Affected before 2.6.12Not affected 5.10.265 through 5.10.Not affected 5.15.216 through 5.15.Not affected 6.1.183 through 6.1.Not affected 6.6.148 through 6.6.Not affected 6.12.101 through 6.12.Not affected 6.18.42 through 6.18.Not affected 7.1.6 through 7.1.*Not affected 7.2 and laterNot affected

Product

Versions

LinuxLinux

1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to before 8180daf2b66155f84ec4f9e3f95488c8a3421716Affected
1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to before 189a550eb7e1dc10018718ddfc46d003ffe58653Affected
1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to before 1be09d175b627fad7f6bec7ad27b8a4a99863912Affected
1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to before eb3836eab47487823f362e6985e170a1e15f20fdAffected
1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to before 44401f7dd9940ced7098930ef64f5a332f279fc2Affected
1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to before 5d07b178bef511d69558cfc89fe1129258dc39f8Affected
1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to before 0e37bbd6d617eb52bace49390e99eaedc1af73ceAffected
1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to before ee7f9bb9320add61f7b367d7e6cd55e3a3a4d65dAffected

LinuxLinux

2.6.12Affected
before 2.6.12Not affected
5.10.265 through 5.10.*Not affected
5.15.216 through 5.15.*Not affected
6.1.183 through 6.1.*Not affected
6.6.148 through 6.6.*Not affected
6.12.101 through 6.12.*Not affected
6.18.42 through 6.18.*Not affected
7.1.6 through 7.1.*Not affected
7.2 and laterNot affected

References

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