CVE-2025-39964

LOW

Linux Kernel - Denial of Service via Concurrent af_alg Socket Writes

Title source: llm
STIX 2.1

Exploitation Summary

EIP tracks 1 public exploit for CVE-2025-39964. PoCs published by n1k0oowang.

AI-analyzed exploit summary This exploit targets a Linux kernel vulnerability (CVE-2025-39964) by leveraging AF_ALG socket operations to achieve local privilege escalation (LPE). It employs memory spraying, KASLR bypass, and core_pattern manipulation to execute arbitrary code with root privileges.

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.

Exploits (1)

nomisec WORKING POC 1 stars
by n1k0oowang · poc
https://github.com/n1k0oowang/CVE-2025-39964_EXP

This exploit targets a Linux kernel vulnerability (CVE-2025-39964) by leveraging AF_ALG socket operations to achieve local privilege escalation (LPE). It employs memory spraying, KASLR bypass, and core_pattern manipulation to execute arbitrary code with root privileges.

Classification
Working Poc 95%
Attack Type
Lpe
Complexity
Complex
Reliability
Racy
Target: Linux Kernel (version not explicitly specified)
No auth needed
Prerequisites: Local access to the vulnerable system · Kernel with AF_ALG socket support · Ability to execute arbitrary code
devstral-2 · analyzed Feb 16, 2026 Full analysis →

Scores

CVSS v3 3.3
EPSS 0.0003
EPSS Percentile 9.2%
Attack Vector LOCAL
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

Status published
Products (24)
linux/Kernel 2.6.38 - 5.10.245linux
linux/Kernel 5.11.0 - 5.15.194linux
linux/Kernel 5.16.0 - 6.1.154linux
linux/Kernel 6.13.0 - 6.16.9linux
linux/Kernel 6.2.0 - 6.6.108linux
linux/Kernel 6.7.0 - 6.12.49linux
Linux/Linux < 2.6.38
Linux/Linux 2.6.38
Linux/Linux 5.10.245 - 5.10.*
Linux/Linux 5.15.194 - 5.15.*
... and 14 more
Published Oct 13, 2025
Tracked Since Feb 18, 2026