Answer in brief
CVE-2026-123612 records a Medium severity (CVSS 4.6) vulnerability in rustls 0.23.44 and 0.23.45 ECH Rejection Application Data Disclosure. The current sources do not mark it as known exploited. The current feed maps rustls/rustls (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 4.6. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps rustls/rustls (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| rustls/rustlsgeneric | >=0.23.44 <0.23.46 | 0.23.46 |
Published upstream
Nov 8, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Nov 8, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Nov 8, 2026
rustls 0.23.44 and 0.23.45 contain an information disclosure vulnerability that sends application data buffered before the handshake completes to the client-facing server when Encrypted Client Hello is rejected. Because start_traffic() queues plaintext from ClientConnection::writer() before sending the ech_required alert, the authenticated public_name server receives data intended for the inner server.
Quoted source text, attributed separately from HOL analysis.