CVSS 4.0
4.1 mediumCVSS:4.0/AV:L/AC:H/AT:P/PR:H/UI:P/VC:H/VI:N/VA:N/SC:N/SI:N/SA:NCVE-2026-123609
Medium (4.1) in rustls rustls. EPSS 0.1% estimated probability of exploitation activity in the next 30 days. Fixed in rustls 0.23.46, 0.24.0-dev.2.
On this page
Rustls before 0.23.46 and 0.24.0-dev.1 before 0.24.0-dev.2 contains an information disclosure vulnerability where derived Debug formatting of client session values exposes secret key material. Custom ClientSessionStore implementations that log Tls12ClientSessionValue or Tls13ClientSessionValue can leak TLS 1.2 master secrets or TLS 1.3 resumption PSKs to log readers.
Severity
CVSS 3.1
4.0 mediumCVSS:3.1/AV:L/AC:H/PR:H/UI:R/S:U/C:H/I:N/A:N- EPSS
- 0.1% estimated probability of exploitation activity in the next 30 days; 1st percentile. Scored 2026-11-10. A forecast for this CVE across the internet, not for your own systems.
- CWE
- CWE-212 Improper Removal of Sensitive Information Before Storage or Transfer
- Published
- NVD analysis
- Awaiting analysis
- Record from
- the NVD, synced
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Affected
Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| rustls | before 0.23.46 |
| rustls | from 0.24.0-dev.1 before 0.24.0-dev.2 |
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-c8m5-c952-6cm4 | crates.io | rustls | <0.23.46 | 0.23.46 |
| GHSA-c8m5-c952-6cm4 | crates.io | rustls | >=0.24.0-dev.1 <0.24.0-dev.2 | 0.24.0-dev.2 |
| RUSTSEC-2026-0346 | crates.io | rustls | >=0.21.0 <0.23.46 | 0.23.46 |
Linux distributions
| Distribution | Release | Package | Fixed in | Advisory |
|---|---|---|---|---|
| Debian | 12, 13, 14 | rust-rustls | no fix listed | DEBIAN-CVE-2026-123609 |
| Ubuntu | 24.04:LTS, 26.04:LTS, 26.10 | rust-rustls | no fix listed | UBUNTU-CVE-2026-123609 |
From the distributions' data via OSV.dev: the Debian Security Tracker; Ubuntu Security Notices © Canonical Ltd., CC BY-SA 4.0. Modified: reformatted and linked to CVE records. Credits. On the distributions' own pages: Debian · Ubuntu.
Attack patterns (CAPEC)
- CAPEC-168 Windows ::DATA Alternate Data Stream Severity: Medium
The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits.