9.8

CVE-2026-74493: linux

CVSS: 9.8v3.1CriticalReceived
AliasesUBUNTU-CVE-2026-74493DEBIAN-CVE-2026-74493
Published 15-08-2026Last modified 16-10-2026
Open JSON

Vulnerability summary

CVE-2026-74493 is a critical (CVSS 9.8) vulnerability in linux. EPSS estimates a 0.50% chance of exploitation in the next 30 days, higher than 41.8% of scored vulnerabilities.

Overall risk
70/100
0100
High · default modelHow is this calculated?
CVSS score
9.8/10
010
Critical · v3.1 (CVE.org)
EPSS score
0.50%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 19 · Related 19
OPENSUSE-SU-2026:22091-1SUSE-SU-2026:24179-1SUSE-SU-2026:24181-1SUSE-SU-2026:24182-1SUSE-SU-2026:24184-1SUSE-SU-2026:4640-1

Timeline

  1. 15-08-2026
    PublishedVulnerability first disclosed.
  2. 16-10-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: net/smc: fix socket use-after-free during link group termination __smc_lgr_terminate() drops conns_lock after finding a connection in lgr->conns_all, but before taking a reference on its socket. The connection is embedded in the socket, and its registration reference protects it only while the connection remains in the tree. A concurrent close can unregister the connection and drop that reference, freeing the socket before the termination worker reaches sock_hold(). The race is reachable when close overlaps link group termination. Local stress testing reproduced the use-after-free and KASAN reported: BUG: KASAN: slab-use-after-free in __smc_lgr_terminate.part.0 [smc] Write of size 4 by task kworker/3:3 Workqueue: events smc_lgr_terminate_work [smc] __smc_lgr_terminate.part.0 [smc] The socket was allocated by smc_create(), freed through slab_free_after_rcu_debug(), and was followed by: refcount_t: addition on 0; use-after-free. __smc_lgr_terminate.part.0 [smc] Take the socket reference while conns_lock still protects the tree entry. The unregister path then cannot drop the last reference until termination has finished using the socket.

CVSS metrics

4 scores · 4 sources · 1 version

EPSS trend

Probability

0.50%

Chance of exploitation in the next 30 days

Percentile

42%

Versus all other CVEs

30-day change

0.00 pp

From 0.50% on 21-09-2026

21-09-202621-10-2026
EPSS score
0.50%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

No weakness data has been published for this record.

Affected systems

Ubuntu157 products
  • linux< 5.15.0-198.208 | All versions (No fix recorded)
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-aws< 5.15.0-1117.124 | All versions (No fix recorded)
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Debian2 products
  • linux< 6.1.187-1 | < 6.12.105-1 | < 7.1.8-1
  • linux-6.12< 6.12.107-1~deb12u1
Linux1 product
  • linux≥ 69318b5215f2dc32c345a3d65b98b4b1bf29c007, < ff44f2df57fb5560bdc75eb977867643e764a262 | ≥ 69318b5215f2dc32c345a3d65b98b4b1bf29c007, < 9fb17c95b8f0683570fca1fb2792264147af937a | ≥ 69318b5215f2dc32c345a3d65b98b4b1bf29c007, < bea8dc14de2d56aca749d368563e6888217710a5 | ≥ 69318b5215f2dc32c345a3d65b98b4b1bf29c007, < 5a42f162b857019a4c10ff687dc3bcdf51831865 | ≥ 69318b5215f2dc32c345a3d65b98b4b1bf29c007, < 281c103a8eaed59001ce952f231df1b07674215a | ≥ 69318b5215f2dc32c345a3d65b98b4b1bf29c007, < f807a63d0d95680c34f677700da9148a07d7c78f | ≥ 69318b5215f2dc32c345a3d65b98b4b1bf29c007, < f0541a775d04c88e90ba448e35ce0d743512822a | ≥ 69318b5215f2dc32c345a3d65b98b4b1bf29c007, < f621d6ebeebb6374342571e4ddf45fdbc420f6cd | 5.5

3 vendors · 160 products

References

20 links
Show all 20 references