CVE-2026-97985EPSS p5.5%
CVE-2026-97985CVE-2026-97985
Description
In the Linux kernel, the following vulnerability has been resolved:
af_unix: Update last skb marker in manage_oob().
Fahad Alharbi reported that blocking recv(MSG_PEEK) could hog CPU
due to OOB skb.
In the following cases, manage_oob() skips OOB skb(s) and returns
NULL for the last recv(MSG_PEEK):
socketpair(AF_UNIX, SOCK_STREAM, 0, sk);
1) skb -> OOB skb -> NULL
send(sk[0], "ab", 2, MSG_OOB);
recv(sk[1], buf, 0, MSG_PEEK);
2) skb -> consumed OOB skb -> NULL
send(sk[0], "ab", 2, MSG_OOB);
recv(sk[1], buf, 1, MSG_OOB);
recv(sk[1], buf, 0, MSG_PEEK);
3) consumed OOB skb -> OOB skb -> NULL
send(sk[0], "a", 1, MSG_OOB);
recv(sk[1], buf, 0, MSG_OOB);
send(sk[0], "b", 1, MSG_OOB);
recv(sk[1], buf, 1, MSG_PEEK);
Then, @copied is 0 in unix_stream_read_generic() (zero-length buffer,
or non-OOB skb is not yet consumed), and unix_stream_data_wait() is
called.
However, it returns immediately because @last is not updated in
unix_stream_r
Scoring
| EPSS | 0.17% probability of exploitation · percentile 5.5% · 2026-10-05T12:00:23Z |
| Last modified | 2026-09-25 |