rxrpc: serialize kernel accept preallocation with socket teardown
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Partial Red Hat: 2 without a fix
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat.
Summary
In the Linux kernel, the following vulnerability has been resolved: rxrpc: serialize kernel accept preallocation with socket teardown rxrpc_kernel_charge_accept() reads rx->backlog without any socket/backlog synchronization and passes that raw pointer into rxrpc_service_prealloc_one(). A concurrent rxrpc_discard_prealloc() sets rx->backlog = NULL and frees the backlog rings, so a kernel preallocation worker can keep using a freed struct rxrpc_backlog while updating *_backlog_head/tail and array slots. Serialize the state check and backlog lookup with the socket lock, and reject kernel preallocation once teardown has disabled listening or discarded the service backlog.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
- Fix · CNA Linux (Linux) Fixed in 5.10.266, 5.15.217, 6.1.184, 6.6.148, 6.12.101, 6.18.40, 7.1.5, 7.2
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 10 | Affected | No fix yet |
| Red Hat Enterprise Linux 9 | Affected | No fix yet |
Not affected: 3 products
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
Timeline
- 2026-10-02 Threatist record created from CVE-2026-74436
- 2026-10-03 Alias added: GHSA-c43x-9gq9-q65m
- 2026-10-13 EPSS moved to the below the 50th percentile
- 2026-10-18 CISA SSVC decision points changed
References
Other 8
- https://git.kernel.org/stable/c/d6207326b4ca0ae1041281b6af9df53f8080669a
- https://git.kernel.org/stable/c/11b429b84c87cb5a0152f14e7d6cb649ed363901
- https://git.kernel.org/stable/c/c20d983968f239574290cf804a58cde18ad1c559
- https://git.kernel.org/stable/c/0337cdba0c477f176c0459bed012109453184573
- https://git.kernel.org/stable/c/dfa0b2bbc5e50119f89c6b5407faa5ed86dfa7c5
- https://git.kernel.org/stable/c/35a967ff8b24db09ee429c39c5b5e6571639997d
- https://git.kernel.org/stable/c/1741378a7a83dfd8e53a9196730df709b903cd33
- https://git.kernel.org/stable/c/dc175389b18c29a5303ee83169ec653adfae3e17
More Linux vulnerabilities
- TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
- TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
- TI-2021-02452 Incorrect authorization in Ubuntu linux kernel KEVCVSS 3.1HIGH 8.8
- TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
- TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
- TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
Sources
- CVE-2026-74436 · CVE Program
- CVE-2026-74436 · NVD
- FIRST EPSS
- GHSA-c43x-9gq9-q65m · GitHub Advisory Database · CC BY 4.0
- CVE-2026-74436 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences