CVE-2026-123613

medium

Description

Rustls from 0.23.13 before 0.23.45 accepts TLS 1.3 handshake messages at the wrong encryption level when they follow a key-changing message in the same record, because Deframer::aligned does not enforce RFC 8446 record-boundary alignment. A peer or on-path attacker can pack a plaintext EncryptedExtensions with the ServerHello, which rustls accepts unencrypted.

References

https://www.vulncheck.com/advisories/rustls-0.23.13-before-0.23.45-tls-1.3-handshake-encryption-level-bypass

https://github.com/rustls/rustls/security/advisories/GHSA-2mjx-qc3c-rqvc

https://github.com/rustls/rustls/commit/5046bdf8a612b35a2c1a9e168054c1d5c65e7dd7

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-119372

Details

Source: Mitre, NVD

Published: 2026-11-08

Updated: 2026-11-08

Risk Information

CVSS v2

Base Score: 5

Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:N/A:N

Severity: Medium

CVSS v3

Base Score: 5.3

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

Severity: Medium

CVSS v4

Base Score: 6.9

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N

Severity: Medium

EPSS

EPSS: 0.00156