xsk: Fix race condition in AF_XDP generic RX path
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Partial Red Hat: 3 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: xsk: Fix race condition in AF_XDP generic RX path Move rx_lock from xsk_socket to xsk_buff_pool. Fix synchronization for shared umem mode in generic RX path where multiple sockets share single xsk_buff_pool. RX queue is exclusive to xsk_socket, while FILL queue can be shared between multiple sockets. This could result in race condition where two CPU cores access RX path of two different sockets sharing the same umem. Protect both queues by acquiring spinlock in shared xsk_buff_pool. Lock contention may be minimized in the future by some per-thread FQ buffering. It's safe and necessary to move spin_lock_bh(rx_lock) after xsk_rcv_check(): * xs->pool and spinlock_init is synchronized by xsk_bind() -> xsk_is_bound() memory barriers. * xsk_rcv_check() may return true at the moment of xsk_release() or xsk_unbind_dev(), however this will not cause any data races or race conditions. xsk_unbind_dev() removes xdp socket from all maps and waits for completion of all outstanding rx operations. Packets in RX path will either complete safely or drop.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Linux | Linux | 5.1.20 to before 5.2; 5.2.3 to before 5.3 | 5.2, 5.3 | Patch available | CNA |
| Linux | Linux | 5.3 and later | 6.1.164, 6.6.123, 6.12.28, 6.14.6, 6.15 | Patch available | CNA |
- Linux VendorLinux Affected 5.1.20 to before 5.2; 5.2.3 to before 5.3 Fixed in 5.2, 5.3 Patch available CNA
- Linux VendorLinux Affected 5.3 and later Fixed in 6.1.164, 6.6.123, 6.12.28, 6.14.6, 6.15 Patch available CNA
CPE configurations NVD · 5
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | 5.1.20 to before 5.2; 5.2.3 to before 6.12.28; 6.13 to before 6.14.6 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.15:rc1:*:*:*:*:*:* | 6.15 rc1 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.15:rc2:*:*:*:*:*:* | 6.15 rc2 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.15:rc3:*:*:*:*:*:* | 6.15 rc3 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.15:rc4:*:*:*:*:*:* | 6.15 rc4 | Vulnerable | Linux |
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 5.1.20 to before 5.2; 5.2.3 to before 6.12.28; 6.13 to before 6.14.6 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.15:rc1:*:*:*:*:*:* Versions 6.15 rc1 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.15:rc2:*:*:*:*:*:* Versions 6.15 rc2 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.15:rc3:*:*:*:*:*:* Versions 6.15 rc3 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.15:rc4:*:*:*:*:*:* Versions 6.15 rc4 Vulnerable ·Linux
Remediation
- Fix · CNA Linux (Linux) Fixed in 5.2, 5.3
- Fix · CNA Linux (Linux) Fixed in 6.1.164, 6.6.123, 6.12.28, 6.14.6, 6.15
Vendor assessments
Red Hat
Red Hat rating: Low. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 10 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 8 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 9 | Affected | No fix yet: Fix deferred |
Not affected: 2 products
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
Timeline
- 2026-10-02 Threatist record created from CVE-2025-37920
- 2026-10-03 Alias added: GHSA-4qc6-52f6-6vgr
- 2026-10-16 CISA SSVC decision points changed
References
Patch 5
- https://git.kernel.org/stable/c/975b372313dc018b9bd6cc0d85d188787054b19e
- https://git.kernel.org/stable/c/b6978c565ce33658543c637060852434b4248d30
- https://git.kernel.org/stable/c/65d3c570614b892257dc58a1b202908242ecf8fd
- https://git.kernel.org/stable/c/75a240a3e8abf17b9e00b0ef0492b1bbaa932251
- https://git.kernel.org/stable/c/a1356ac7749cafc4e27aa62c0c4604b5dca4983e
More Linux Kernel 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-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
- TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
Sources
- CVE-2025-37920 · CVE Program
- CVE-2025-37920 · NVD
- FIRST EPSS
- GHSA-4qc6-52f6-6vgr · GitHub Advisory Database · CC BY 4.0
- CVE-2025-37920 · Red Hat security data · CC BY 4.0
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