smb/client: fix out-of-bounds read in symlink_data()

Summary

In the Linux kernel, the following vulnerability has been resolved: smb/client: fix out-of-bounds read in symlink_data() Since smb2_check_message() returns success without length validation for the symlink error response, in symlink_data() it is possible for iov->iov_len to be smaller than sizeof(struct smb2_err_rsp). If the buffer only contains the base SMB2 header (64 bytes), accessing err->ErrorContextCount (at offset 66) or err->ByteCount later in symlink_data() will cause an out-of-bounds read.

Timeline

1. May 28, 2026, 9:36 AM UTCCVE published
2. Oct 16, 2026, 3:20 PM UTCCISA SSVC assessment

   Exploitation: none · Automatable: yes · Technical impact: partial

3. Oct 19, 2026, 7:36 PM UTCRecord last updated

Affected versions

• Linux Linux

  From 76894f3e2f71177747b8b4763fb180e800279585 · fixed in 2be11faf79e49fb8250a181ff0b4d2b2f084af83; From 76894f3e2f71177747b8b4763fb180e800279585 · fixed in ef6495d4df6e7af8f3de67e65150881c880f696c; From 76894f3e2f71177747b8b4763fb180e800279585 · fixed in 15dc0a4de743a1aaa7b859b3aea79f08c695396c; From 76894f3e2f71177747b8b4763fb180e800279585 · fixed in b8c8a704f0bc133deb171f6aeb6f3a684203e212; From 76894f3e2f71177747b8b4763fb180e800279585 · fixed in b9561402489d41149f63e001a74384863b7b30a6; From 76894f3e2f71177747b8b4763fb180e800279585 · fixed in d62b8d236fab503c6fec1d3e9a38bea71feaca20; From 6.0.16 · fixed in 6.1

• Linux Linux

  6.1

• KernelLinux

  From 6.1.0 · fixed in 6.1.175; From 6.2.0 · fixed in 6.6.140; From 6.7.0 · fixed in 6.12.88; From 6.13.0 · fixed in 6.18.30; From 6.19.0 · fixed in 7.0.7

References 6