CVE-20XX-?

CVE-2025-39682

9.8 CRITICAL 3% exploit odds exploited in the wild Fix listed Other OS & kernel

What it is

In the Linux kernel, the following vulnerability has been resolved: tls: fix handling of zero-length records on the rx_list Each recvmsg() call must process either - only contiguous DATA records (any number of them) - one non-DATA record If the next record has different type than what has already been processed we break out of the main processing loop. If the record has already been decrypted (which may be the case for TLS 1.3 where we don't know type until decryption) we queue the pending record to the rx_list. Next recvmsg() will pick it up from there. Queuing the skb to rx_list after zero-copy decrypt is not possible, since in that case we decrypted directly to the user space buffer, and we don't have an skb to queue (darg.skb points to the ciphertext skb for access to metadata like length). Only data records are allowed zero-copy, and we break the processing loop after each non-data record. So we should never zero-copy and then find out that the record type has changed. The corner case we missed is when the initial record comes from rx_list, and it's zero length.

At a glance

Exploitability
Can be exploited over the network without logging in. High risk of data exposure, data tampering, service disruption.
In the wild
CISA lists this as exploited in real attacks. Treat as urgent.
Fix
A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

  1. ReservedThe CVE id was reserved by its CNA
  2. PublishedDisclosed publicly on CVE.org and NVD
  3. 2026-09-18 Exploited in the wildAdded to CISA's Known Exploited Vulnerabilities list
  4. 2026-09-21 Remediation deadlineCISA's due date for federal agencies to fix it
  5. Last updatedMost recent change to the record

Details

Published
Last modified
Added to CISA KEV
2026-09-18
Exploit probability
3.2% · EPSS, next 30 days
Weakness
CWE-754
Record status
Analyzed

Affected

Attack profile CVSS 3.1 · 9.8

Attack vector
Network
Complexity
Low
Privileges needed
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
Raw vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Meme: I wake up, CVE-2025-39682
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Fix and advisories

References

NVD record · CVE.org record