high Known exploitedREV. 01
CVE-2025-39964Linux Kernel — Race Condition in Crypto Socket Writes
A race condition in the Linux kernel's user-space crypto socket interface lets a local user issue overlapping writes to one socket, corrupting its internal state and crashing or destabilizing the host. Exploitation has been observed in the wild.
Read the risk
THE VITAL STATS- CVSS score
- 5.5/ 10 CVSS v3.1
- EPSS probability
- 1% Likelihood of exploitation
- Attack complexity
- Low Conditions needed to exploit
- Known exploited
- Yes — CISA KEV
- CVE published
- 2025-10-13
- Added to KEV
- 2026-09-18
- Exploit published
- Not recorded
- Confidence
- medium
- Kill chain
- impact
- MITRE ATT&CK
- T1499
- Severity
- high
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attacker needsLocal access as a low-privileged user able to open kernel crypto user-space sockets
Behind the card
5 REFERENCES- 01CVE recordNVD recordnvd.nist.gov
- 02CISACISA Known Exploited Vulnerabilities catalogcisa.gov
- 03Vendor advisorygit.kernel.orggit.kernel.org
- 04Vendor advisorygit.kernel.orggit.kernel.org
- 05Vendor advisorygit.kernel.orggit.kernel.org
Field-level provenanceTRACE THE SOURCES +
Which source supports each field, when it was retrieved, and who extracted it.
| Fields | Source | Retrieved | Extractor | Confidence |
|---|---|---|---|---|
| cvss, exploitation.attack_complexity, exploitation.exploit_available, references, published_at | nvd.nist.gov | 2026-09-20 | scrty-crds-pipeline/0.1 | high |
| exploitation.known_exploited, exploitation.kev_added | cisa.gov | 2026-09-20 | scrty-crds-pipeline/0.1 | high |
| epss | api.first.org | 2026-09-20 | scrty-crds-pipeline/0.1 | high |
| title, summary, severity, remediation, mitre_attack, kill_chain, recommended_action, confidence, tags, exploitation.prerequisites | nvd.nist.gov | 2026-09-20 | claude-code | high |
| tags | nvd.nist.gov | 2026-09-20 | human | high |
Printing history
THE RECORD- r1Initial base card
First printing. This card has not been reprinted since publication.