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EUVD-2026-344336

European Vulnerability Database identifier assigned by ENISA

Reserved

2026-10-02 07:56

Assigner

ENISA

Alias of

a CVE record, shown under related vulnerabilities. This identifier carries no description, severity or references of its own: they belong to that CVE.

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{
  "assigner": "ENISA",
  "date_reserved": "2026-10-02T07:56:02.702022+00:00",
  "id": "EUVD-2026-344336"
}

CVE-2021-46929 (GCVE-0-2021-46929)

Vulnerability from cvelistv5 – Published: 2024-02-27 09:43 – Updated: 2026-08-05 08:45

Title

sctp: use call_rcu to free endpoint

Summary

In the Linux kernel, the following vulnerability has been resolved: sctp: use call_rcu to free endpoint This patch is to delay the endpoint free by calling call_rcu() to fix another use-after-free issue in sctp_sock_dump(): BUG: KASAN: use-after-free in __lock_acquire+0x36d9/0x4c20 Call Trace: __lock_acquire+0x36d9/0x4c20 kernel/locking/lockdep.c:3218 lock_acquire+0x1ed/0x520 kernel/locking/lockdep.c:3844 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:168 spin_lock_bh include/linux/spinlock.h:334 [inline] __lock_sock+0x203/0x350 net/core/sock.c:2253 lock_sock_nested+0xfe/0x120 net/core/sock.c:2774 lock_sock include/net/sock.h:1492 [inline] sctp_sock_dump+0x122/0xb20 net/sctp/diag.c:324 sctp_for_each_transport+0x2b5/0x370 net/sctp/socket.c:5091 sctp_diag_dump+0x3ac/0x660 net/sctp/diag.c:527 __inet_diag_dump+0xa8/0x140 net/ipv4/inet_diag.c:1049 inet_diag_dump+0x9b/0x110 net/ipv4/inet_diag.c:1065 netlink_dump+0x606/0x1080 net/netlink/af_netlink.c:2244 __netlink_dump_start+0x59a/0x7c0 net/netlink/af_netlink.c:2352 netlink_dump_start include/linux/netlink.h:216 [inline] inet_diag_handler_cmd+0x2ce/0x3f0 net/ipv4/inet_diag.c:1170 __sock_diag_cmd net/core/sock_diag.c:232 [inline] sock_diag_rcv_msg+0x31d/0x410 net/core/sock_diag.c:263 netlink_rcv_skb+0x172/0x440 net/netlink/af_netlink.c:2477 sock_diag_rcv+0x2a/0x40 net/core/sock_diag.c:274 This issue occurs when asoc is peeled off and the old sk is freed after getting it by asoc->base.sk and before calling lock_sock(sk). To prevent the sk free, as a holder of the sk, ep should be alive when calling lock_sock(). This patch uses call_rcu() and moves sock_put and ep free into sctp_endpoint_destroy_rcu(), so that it's safe to try to hold the ep under rcu_read_lock in sctp_transport_traverse_process(). If sctp_endpoint_hold() returns true, it means this ep is still alive and we have held it and can continue to dump it; If it returns false, it means this ep is dead and can be freed after rcu_read_unlock, and we should skip it. In sctp_sock_dump(), after locking the sk, if this ep is different from tsp->asoc->ep, it means during this dumping, this asoc was peeled off before calling lock_sock(), and the sk should be skipped; If this ep is the same with tsp->asoc->ep, it means no peeloff happens on this asoc, and due to lock_sock, no peeloff will happen either until release_sock. Note that delaying endpoint free won't delay the port release, as the port release happens in sctp_endpoint_destroy() before calling call_rcu(). Also, freeing endpoint by call_rcu() makes it safe to access the sk by asoc->base.sk in sctp_assocs_seq_show() and sctp_rcv(). Thanks Jones to bring this issue up. v1->v2: - improve the changelog. - add kfree(ep) into sctp_endpoint_destroy_rcu(), as Jakub noticed.

Severity

7.8 (High)


                        
                          CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2024-09-10 16:02 UTC

Assigner

Linux mitre root Scorecard

References

6 references

URL	Tags
https://git.kernel.org/stable/c/8873140f95d4977bf…
https://git.kernel.org/stable/c/af6e6e58f7ebf86b4…
https://git.kernel.org/stable/c/831de271452b87657…
https://git.kernel.org/stable/c/769d14abd35e0e153…
https://git.kernel.org/stable/c/75799e71df1da1139…
https://git.kernel.org/stable/c/5ec7d18d1813a5bea…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: d25adbeb0cdb860fb39e09cdd025e9cfc954c5ab , < 8873140f95d4977bf37e4cf0d5c5e3f6e34cdd3e (git) Affected: d25adbeb0cdb860fb39e09cdd025e9cfc954c5ab , < af6e6e58f7ebf86b4e7201694b1e4f3a62cbc3ec (git) Affected: d25adbeb0cdb860fb39e09cdd025e9cfc954c5ab , < 831de271452b87657fcf8d715ee20519b79caef5 (git) Affected: d25adbeb0cdb860fb39e09cdd025e9cfc954c5ab , < 769d14abd35e0e153b5149c3e1e989a9d719e3ff (git) Affected: d25adbeb0cdb860fb39e09cdd025e9cfc954c5ab , < 75799e71df1da11394740b43ae5686646179561d (git) Affected: d25adbeb0cdb860fb39e09cdd025e9cfc954c5ab , < 5ec7d18d1813a5bead0b495045606c93873aecbb (git)
Linux	Linux	Affected: 4.14 Unaffected: 0 , < 4.14 (semver) Unaffected: 4.14.261 , ≤ 4.14.* (semver) Unaffected: 4.19.224 , ≤ 4.19.* (semver) Unaffected: 5.4.170 , ≤ 5.4.* (semver) Unaffected: 5.10.90 , ≤ 5.10.* (semver) Unaffected: 5.15.13 , ≤ 5.15.* (semver) Unaffected: 5.16 , ≤ * (original_commit_for_fix)

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JSON

To clipboard

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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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EUVD-2026-344336

CVE-2021-46929 (GCVE-0-2021-46929)

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Nomenclature

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