CVE-2025-39964
Linux Kernel contains a race condition vulnerability which allows concurrent writes to the same AF_ALG socket causing data to be unpredictably interleaved and creating inconsistencies in the socket's internal state.
In the Linux kernel, the following vulnerability has been resolved: crypto: af_alg - Disallow concurrent writes in af_alg_sendmsg Issuing two writes to the same af_alg socket is bogus as the data will be interleaved in an unpredictable fashion. Furthermore, concurrent writes may create inconsistencies in the internal socket state. Disallow this by adding a new ctx->write field that indiciates exclusive ownership for writing.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H- git.kernel.org/stable/c/0f28c4adbc4a97437874c9b669fd7958a8c6d6cePatch
- git.kernel.org/stable/c/1b34cbbf4f011a121ef7b2d7d6e6920a036d5285Patch
- git.kernel.org/stable/c/1f323a48e9b5ebfe6dc7d130fdf5c3c0e92a07c8Patch
- git.kernel.org/stable/c/45bcf60fe49b37daab1acee57b27211ad1574042Patch
- git.kernel.org/stable/c/7c4491b5644e3a3708f3dbd7591be0a570135b84Patch
- git.kernel.org/stable/c/9aee87da5572b3a14075f501752e209801160d3dPatch
- git.kernel.org/stable/c/e4c1ec11132ec466f7362a95f36a506ce4dc08c9Patch
- cert-portal.siemens.com/productcert/html/ssa-019113.htmlThird Party Advisory
- cert-portal.siemens.com/productcert/html/ssa-457936.htmlThird Party Advisory
- cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-39964US Government Resource
Actively exploited. Patch immediately.
- Exploitation
- Confirmed in the wild (CISA KEV)
- Federal remediation deadline
- Overdue by 36 days
- CVSS
- 7.8 HIGH
- EPSS (30-day exploit probability)
- 1.6% · top 25% of all CVEs
- Weakness
- CWE-362
- 1.Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
- 2.Treat as emergency change: patch or isolate internet-facing instances first.
- 3.Hunt for compromise: review logs for the disclosure window, not just from the patch date.
Assessment is derived automatically from the live signals above; verify against your own asset inventory.