CVE-2026-3549

unknown
Published — · Modified —
CVSS v3
CVSS v2
VIR risk

Description

Heap Overflow in TLS 1.3 ECH parsing. An integer underflow existed in ECH extension parsing logic when calculating a buffer length, which resulted in writing beyond the bounds of an allocated buffer. Note that in wolfSSL, ECH is off by default, and the ECH standard is still evolving.

Predictions

Exploit likelihood
20%
Patch ETA

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

vendor Authored 2026-05-27

Vendor advisory: debian — https://security-tracker.debian.org/tracker/CVE-2026-3549

OS impact

OSVersionStatusFixed in
debian debianbookwormaffected
debian debianbullseyeaffected
debian debianforkyfixed5.9.0-0.1
debian debiansidfixed5.9.0-0.1
debian debiantrixieaffected

References

Verify integrity in audit chain (admin only). AS-IS.