Answer in brief
CVE-2026-74589 records a Unknown severity vulnerability in bpf, sockmap: Fix sk_redir use-after-free in send verdict. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=604326b41a6fb9b4a78b6179335decee0365cd8c <41b7da0cb72ca5aa1e62b68dab323d0791fc6bdf || >=604326b41a6fb9b4a78b6179335decee0365cd8c <9b4fbc371a6ecf1b4e43b5a629015cc0830d8de3 || >=604326b41a6fb9b4a78b6179335decee0365cd8c <90a19b0894ba79a699b48cf44421b36fbd566e99 || >=604326b41a6fb9b4a78b6179335decee0365cd8c <d192cff2a37d59206dabe6ec2e60ceac6271f274 || >=604326b41a6fb9b4a78b6179335decee0365cd8c <4c9d9aa809c261dc0490a0e19d675f7e8e4c85bf || >=604326b41a6fb9b4a78b6179335decee0365cd8c <a14e4ef1d90c3418f01b3b6b8fd3a40a0a208a10 || >=604326b41a6fb9b4a78b6179335decee0365cd8c <1cec526cf0a2227395f2c2f4b671cb052ff0b00e || >=604326b41a6fb9b4a78b6179335decee0365cd8c <a76624733730e541e4955fdecf506af2f6b20558 | 41b7da0cb72ca5aa1e62b68dab323d0791fc6bdf, 9b4fbc371a6ecf1b4e43b5a629015cc0830d8de3, 90a19b0894ba79a699b48cf44421b36fbd566e99, d192cff2a37d59206dabe6ec2e60ceac6271f274, 4c9d9aa809c261dc0490a0e19d675f7e8e4c85bf, a14e4ef1d90c3418f01b3b6b8fd3a40a0a208a10, 1cec526cf0a2227395f2c2f4b671cb052ff0b00e, a76624733730e541e4955fdecf506af2f6b20558 |
| Linux/Linuxgeneric | 4.20 | Not reported |
Published upstream
Aug 22, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 22, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 22, 2026
In the Linux kernel, the following vulnerability has been resolved: bpf, sockmap: Fix sk_redir use-after-free in send verdict sk_psock_msg_verdict() takes a socket reference for psock->sk_redir. tcp_bpf_send_verdict() copies that pointer while holding the source socket lock, but does not take a reference for the local copy before dropping the lock around tcp_bpf_sendmsg_redir(). When apply_bytes keeps the cached verdict active, another sendmsg() on the same source socket can consume the remaining bytes and release the cached reference while the first thread still holds only the raw local pointer: CPU 0 CPU 1 sk_redir = psock->sk_redir apply_bytes remains nonzero release_sock(sk) lock_sock(sk) apply_bytes reaches zero psock->sk_redir = NULL release_sock(sk) tcp_bpf_sendmsg_redir(sk_redir) sock_put(sk_redir) tcp_bpf_sendmsg_redir(sk_redir) The final sock_put() can free sk_redir before CPU 0 dereferences it. KASAN reported: BUG: KASAN: slab-use-after-free in tcp_bpf_sendmsg_redir+0xf39/0x1020 Read of size 8 at addr ffff888108537090 by task poc/87 Call Trace: tcp_bpf_sendmsg_redir+0xf39/0x1020 tcp_bpf_sendmsg+0x977/0x1a50 __sys_sendto+0x32c/0x3a0 __x64_sys_sendto+0xdb/0x1b0 Allocated by task 85: sk_prot_alloc+0x56/0x210 sk_clone+0x6f/0x14b0 inet_csk_clone_lock+0x24/0x740 tcp_create_openreq_child+0x25/0x2710 tcp_v4_syn_recv_sock+0x10a/0xe00 Freed by task 0: __kasan_slab_free+0x43/0x70 slab_free_after_rcu_debug+0xa6/0x1e0 rcu_core+0x50a/0x1850 Last potentially related work creation: __sk_destruct+0x3da/0x540 sk_psock_destroy+0x81e/0xab0 process_one_work+0x63a/0x1070 Take a temporary socket reference while the source socket lock still protects psock->sk_redir, and drop it after tcp_bpf_sendmsg_redir() returns. This keeps each unlocked use independent of cached-verdict ownership.
Quoted source text, attributed separately from HOL analysis.