CVE-2026-68143

Summary

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.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < eb3836eab47487823f362e6985e170a1e15f20fdaffected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 44401f7dd9940ced7098930ef64f5a332f279fc2affected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 5d07b178bef511d69558cfc89fe1129258dc39f8affected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 0e37bbd6d617eb52bace49390e99eaedc1af73ceaffected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < ee7f9bb9320add61f7b367d7e6cd55e3a3a4d65daffected
LinuxLinux2.6.12affected
LinuxLinux0 < 2.6.12unaffected
LinuxLinux6.6.148 <= 6.6.*unaffected
LinuxLinux6.12.101 <= 6.12.*unaffected
LinuxLinux6.18.42 <= 6.18.*unaffected
LinuxLinux7.1.6 <= 7.1.*unaffected
LinuxLinux7.2-rc5 <= *unaffected

Weaknesses

References