CVE-2026-123613

EUVD-2026-119372
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.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
VulnCheckCNA
5.3 MEDIUM
NETWORK
LOW
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Base Score
CVSS 3.x
EPSS Score
Percentile: 4.74%
Early Detection
Affected products identified ahead of NVD analysis through intelligence sources (CNA/ADP records, vendor advisories, Enginsight analysis).
VendorProductVersionSource
rustls_projectrustls
0.23.13 ≤
𝑥
< 0.23.45
CNA
Debian logo
Debian Releases
Debian Product
Codename
rust-rustls
bookworm
postponed
forky
0.23.45+ds-1
fixed
sid
0.23.46+ds-1
fixed
trixie
no-dsa
Common Weakness Enumeration
References
https://github.com/rustls/rustls/commit/5046bdf8a612b35a2c1a9e168054c1d5c65e7dd7
https://github.com/rustls/rustls/security/advisories/GHSA-2mjx-qc3c-rqvc
https://www.vulncheck.com/advisories/rustls-0.23.13-before-0.23.45-tls-1.3-handshake-encryption-level-bypass