high Known exploitedREV. 01
CVE-2025-39682Linux Kernel — TLS Zero-Length Record Mishandling
The Linux kernel's in-kernel Transport Layer Security (TLS) receive path mishandles a zero-length record held over from an earlier read, so later records are processed with wrong zero-copy assumptions, letting a local user crash the system or read data they should not.
Read the risk
THE VITAL STATS- CVSS score
- 7.1/ 10 CVSS v3.1
- EPSS probability
- 1% Likelihood of exploitation
- Attack complexity
- Low Conditions needed to exploit
- Known exploited
- Yes — CISA KEV
- CVE published
- 2025-09-05
- Added to KEV
- 2026-09-18
- Exploit published
- Not recorded
- Confidence
- medium
- Kill chain
- unclassified
- MITRE ATT&CK
- —
- Severity
- high
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
Attacker needsLocal access as a low-privileged user on a host that uses in-kernel TLS
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 |
| recommended_action, 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.