ksmbd: fix out-of-bounds write in smb2_get_ea() EA alignment
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 6.1.175, 5.16, 6.6.136, 6.12.84, 6.18.25, and 1 more
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix out-of-bounds write in smb2_get_ea() EA alignment smb2_get_ea() applies 4-byte alignment padding via memset() after writing each EA entry. The bounds check on buf_free_len is performed before the value memcpy, but the alignment memset fires unconditionally afterward with no check on remaining space. When the EA value exactly fills the remaining buffer (buf_free_len == 0 after value subtraction), the alignment memset writes 1-3 NUL bytes past the buf_free_len boundary. In compound requests where the response buffer is shared across commands, the first command (e.g., READ) can consume most of the buffer, leaving a tight remainder for the QUERY_INFO EA response. The alignment memset then overwrites past the physical kvmalloc allocation into adjacent kernel heap memory. Add a bounds check before the alignment memset to ensure buf_free_len can accommodate the padding bytes. This is the same bug pattern fixed by commit beef2634f81f ("ksmbd: fix potencial OOB in get_file_all_info() for compound requests") and commit fda9522ed6af ("ksmbd: fix OOB write in QUERY_INFO for compound requests"), both of which added bounds checks before unconditional writes in QUERY_INFO response handlers.
Timeline
- CVE published
- Record last updated
Affected versions
- Linux Linux
From 9f297df20d93411c0b4ddad7f88ba04a7cd36e77 · fixed in ddbbc8b2a09dd2cfed90871313e3691ae1db08a2; From e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d · fixed in ffbce350c6fd1e99116ea57383b9031717e36d3b; From e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d · fixed in 98f3de6ef4efbd899348d333f0902dc4ff14380c; From e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d · fixed in 790304c02bf9bd7b8171feda4294d6e62d32ae8f; From e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d · fixed in 922d48fe8c19f388ffa2f709f33acaae4e408de2; From e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d · fixed in 30010c952077a1c89ecdd71fc4d574c75a8f5617; From 6.1.71 · fixed in 6.1.175; From 5.15.145 · fixed in 5.16
- Linux Linux
6.6
- KernelLinux
fixed in 6.1.175; From 6.2.0 · fixed in 6.6.136; From 6.6.0 · fixed in 6.12.84; From 6.7.0 · fixed in 6.18.25; From 6.13.0 · fixed in 7.0.2