Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.
Linux Linux — sctp: do asoc update earlier in sctp_sf_do_dupcook_a
AV AC PR UI S C I A CVSS EPSS %ile KEV
L L L N U H H H 7.8 .0074 51.7 —
AFFECTED
Product Versions Fixed
Linux db8bf823e70f239372c62f13e4eb6f08a1665e8c – —
Linux 5.7 – 4.19.191
TIMELINE
Feb 27 Reserved by Linux
Feb 28 Published (CNA: Linux)
Aug 4 RESCORED — CVE-2021-46999 (Linux). CVSS 9.8 → 7.8 (NVD).
Description
In the Linux kernel, the following vulnerability has been resolved:
sctp: do asoc update earlier in sctp_sf_do_dupcook_a
There's a panic that occurs in a few of envs, the call trace is as below:
[] general protection fault, ... 0x29acd70f1000a: 0000 [#1] SMP PTI
[] RIP: 0010:sctp_ulpevent_notify_peer_addr_change+0x4b/0x1fa [sctp]
[] sctp_assoc_control_transport+0x1b9/0x210 [sctp]
[] sctp_do_8_2_transport_strike.isra.16+0x15c/0x220 [sctp]
[] sctp_cmd_interpreter.isra.21+0x1231/0x1a10 [sctp]
[] sctp_do_sm+0xc3/0x2a0 [sctp]
[] sctp_generate_timeout_event+0x81/0xf0 [sctp]
This is caused by a transport use-after-free issue. When processing a
duplicate COOKIE-ECHO chunk in sctp_sf_do_dupcook_a(), both COOKIE-ACK
and SHUTDOWN chunks are allocated with the transort from the new asoc.
However, later in the sideeffect machine, the old asoc is used to send
them out and old asoc's shutdown_last_sent_to is set to the transport
that SHUTDOWN chunk attached to in sctp_cmd_setup_t2(), which actually
belongs to the new asoc. After the new_asoc is freed and the old asoc
T2 timeout, the old asoc's shutdown_last_sent_to that is already freed
would be accessed in sctp_sf_t2_timer_expire().
Thanks Alexander and Jere for helping dig into this issue.
To fix it, this patch is to do the asoc update first, then allocate
the COOKIE-ACK and SHUTDOWN chunks with the 'updated' old asoc. This
would make more sense, as a chunk from an asoc shouldn't be sent out
with another asoc. We had fixed quite a few issues caused by this.
Lifecycle
Complete event history — 3 events, chronological
| Date | Event | Detail |
| February 27, 2024 | Reserved | Reserved by Linux |
| February 28, 2024 | Published | Published (CNA: Linux) |
| August 4, 2026 | RESCORED | RESCORED — CVE-2021-46999 (Linux). CVSS 9.8 → 7.8 (NVD). |
Affected
Affected products and packages — 2 rows
| Vendor | Product / Package | Ecosystem | Version introduced | Fixed |
| Linux | Linux | — | db8bf823e70f239372c62f13e4eb6f08a1665e8c | — |
| Linux | Linux | — | 5.7 | 4.19.191 |
About this page
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2021-46999 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, August 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.