CVE-2026-123609: rustls · Improper Removal of Sensitive Information Before Storage or Transfer
Affects rustlsSource CVE Database V5
Not known to be exploited · CVSS 4.1 Medium : upgrade to 0.24.0-dev.2 or 0.23.46 when convenient.
Data as of 8 Nov 2026, 01:51 UTC
Thin evidence
One scorer or none| CNA (VulnCheck) | CVSS 4.0 | 4.1 |
|---|---|---|
| CNA (VulnCheck) | CVSS 3.1 | 4.0 |
- Patch
- Available – fixed in 0.24.0-dev.2, 0.23.46
CVSS:4.0/AV:L/AC:H/AT:P/PR:H/UI:P/VC:H/VI:N/VA:N/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 8 Nov 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 7 Nov 2026.
What to do
Upgrade rustls to 0.24.0-dev.2 or 0.23.46.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| rustlsrustls | Affected
| Fixed in
|
| rustlsrustls | Affected
| Fixed in
|
crates.iorustlspkg:cargo/rustlsOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Upgrade rustls to version 0.23.46 or later, or to 0.24.0-dev.2 or later, where this vulnerability is fixed. Avoid logging client session values using derived Debug formatting in custom ClientSessionStore implementations until patched versions are deployed.
Description
CVE-2026-123609 is an information disclosure vulnerability in rustls versions before 0.23.46 and 0.24.0-dev.1 before 0.24.0-dev.2. The flaw arises from derived Debug formatting of client session values, which can expose secret key material. Custom ClientSessionStore implementations that log Tls12ClientSessionValue or Tls13ClientSessionValue risk leaking TLS 1.2 master secrets or TLS 1.3 resumption PSKs to anyone with access to the logs.