nervosnetwork / nervosnetwork/ckb

RUSTSEC-2026-0285: TLS 1.3 handshake messages incorrectly accepted across encryption level boundaries

Open
#5,328 0 comments 0 reactions 0 assignees View on GitHub
Dominant language
Rust
Stars
1.2k
Forks
266
Avg merge
10d 5h
Merged PRs (30d)
4

Description

> TLS 1.3 handshake messages incorrectly accepted across encryption level boundaries

| Details | |
| ------------------- | ---------------------------------------------- |
| Package | `rustls` |
| Version | `0.23.38` |
| URL | [https://github.com/rustls/rustls/security/advisories/GHSA-2mjx-qc3c-rqvc](https://github.com/rustls/rustls/security/advisories/GHSA-2mjx-qc3c-rqvc) |
| Date | 2026-09-14 |
| Patched versions | `>=0.23.45` |
| Unaffected versions | `<0.23.13` |

Rustls accepted TLS 1.3 handshake messages sent at the wrong encryption level
when they followed a key-changing message in the same record. For example,
a plaintext `EncryptedExtensions` message packed into the same record as the
`ServerHello` was accepted.

RFC 8446 section 5.1 requires that handshake messages do not span key changes,
and that implementations terminate the connection with an "unexpected_message"
alert if they do.

The handshake transcript is still authenticated, so a network-position attacker
cannot use this to alter or complete a handshake; the practical effect is that
a peer could send handshake messages that should be encrypted in plaintext
without rustls rejecting the connection.

This is functionally the same bug as Go's
[GO-2026-4340](https://pkg.go.dev/vuln/GO-2026-4340) (CVE-2025-61730).

See [advisory page](https://rustsec.org/advisories/RUSTSEC-2026-0285.html) for additional details.

Contributor guide

Open the contributing guide

Research direction

Locate where the repository declares the rustls dependency and compare its current version with the advisory's affected and patched versions. Update it to at least 0.23.45, then run the repository's dependency and test checks to confirm the vulnerable version is no longer used and existing behavior remains intact.

Written by the indexing model from the issue text.

Assessment

Tech stack
rust
Domain
security
Issue type
Bug
Difficulty
2/5
Estimated time
1-3 hours
Activity status
Active
Clarity
Mostly clear
Newbie friendliness
58/100

Get new issues in your inbox

A short digest of beginner-friendly GitHub issues.