CVE-2025-39964
Last modified
CVE-2025-39964 is a medium-severity vulnerability rated 5.5/10 on the CVSS scale. 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.. CISA has confirmed active exploitation in the wild. EPSS estimates a 0.32% chance of exploitation in the next 30 days.
Description
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.
Metrics
Exploitation Status
This vulnerability is listed in CISA’s Known Exploited Vulnerabilities catalog, confirming active exploitation in the wild. Federal agencies must remediate by .
Weakness Enumeration
Affected Software
| Vendor | Product | Versions | Update |
|---|---|---|---|
| Linux | Linux Kernel | >= 2.6.38, < 5.10.245 | — |
| Linux | Linux Kernel | >= 5.11, < 5.15.194 | — |
| Linux | Linux Kernel | >= 5.16, < 6.1.154 | — |
| Linux | Linux Kernel | >= 6.2, < 6.6.108 | — |
| Linux | Linux Kernel | >= 6.7, < 6.12.49 | — |
| Linux | Linux Kernel | >= 6.13, < 6.16.9 | — |
| Linux | Linux Kernel | 6.17 | Rc1 |
| Siemens | Simatic S7-1500 Cpu 1518-4 Pn\/Dp Mfp Firmware | >= 3.1.6 | — |
| Siemens | Simatic S7-1500 Cpu 1518f-4 Pn\/Dp Mfp Firmware | >= 3.1.6 | — |
References
- https://cert-portal.siemens.com/productcert/html/ssa-019113.htmlThird Party Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-39964US Government Resource
Timeline
- Published
- Last Modified
- Status
- Analyzed
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How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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