CVE-2026-46119 PUBLISHED

libceph: Fix slab-out-of-bounds access in auth message processing

Assigner: Linux
Reserved: 13.05.2026 Published: 28.05.2026 Updated: 30.05.2026

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

libceph: Fix slab-out-of-bounds access in auth message processing

If a (potentially corrupted) message of type CEPH_MSG_AUTH_REPLY contains a positive value in its result field, it is treated as an error code by ceph_handle_auth_reply() and returned to handle_auth_reply(). Thereafter, an attempt is made to send the preallocated message of type CEPH_MSG_AUTH, where the returned value is interpreted as the size of the front segment to send. If the result value in the message is greater than the size of the memory buffer allocated for the front segment, an out-of-bounds access occurs, and the content of the memory region beyond this buffer is sent out.

This patch fixes the issue by treating only negative values in the result field as errors. Positive values are therefore treated as success in the same way as a zero value. Additionally, a BUG_ON is added to __send_prepared_auth_request() comparing the len parameter to front_alloc_len to prevent sending the message if it exceeds the bounds of the allocation and to make it easier to catch any logic flaws leading to this.

Metrics

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
CVSS Score: 9.1

Product Status

Vendor Linux
Product Linux
Versions Default: unaffected
  • affected from 4e7a5dcd1bbab6560fbc8ada29a840e7a20ed7bc to 2ae0afd98432536562fa8261538ae795446f0589 (excl.)
  • affected from 4e7a5dcd1bbab6560fbc8ada29a840e7a20ed7bc to 408e85ee708b6aa03eeb0220ffa0915f4d407181 (excl.)
  • affected from 4e7a5dcd1bbab6560fbc8ada29a840e7a20ed7bc to b7df9fbd4869fdfe09a3f501ffd228486521e062 (excl.)
  • affected from 4e7a5dcd1bbab6560fbc8ada29a840e7a20ed7bc to 8517b6c8d2c759918ba0058cb6c7e14d59643202 (excl.)
  • affected from 4e7a5dcd1bbab6560fbc8ada29a840e7a20ed7bc to 1c439de70b1c3eb3c6bffa8245c16b9fc318f114 (excl.)
Vendor Linux
Product Linux
Versions Default: affected
  • Version 2.6.34 is affected
  • unaffected from 0 to 2.6.34 (excl.)
  • unaffected from 6.6.140 to 6.6.* (incl.)
  • unaffected from 6.12.88 to 6.12.* (incl.)
  • unaffected from 6.18.30 to 6.18.* (incl.)
  • unaffected from 7.0.7 to 7.0.* (incl.)
  • unaffected from 7.1-rc1 to * (incl.)

References