CVE-2026-93601
Publication date 21 September 2026
Last updated 21 September 2026
Ubuntu priority
Description
rustls-webpki (the Rust webpki fork used by rustls) versions >= 0.101.0 and prior to 0.103.12 and 0.104.0-alpha.6 incorrectly accepted permitted-subtree DNS name constraints for certificates asserting a wildcard name. For example, a name constraint of accept.example.com was treated as satisfied by a certificate for *.example.com, which could feasibly assert reject.example.com — a name outside the permitted subtree. Because name constraints are restrictions applied to otherwise properly issued certificates, the issue is only reachable after signature verification succeeds and requires a misissued wildcard certificate to exploit.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| rust-rustls-webpki | 26.04 LTS resolute |
Needs evaluation
|
| 24.04 LTS noble |
Needs evaluation
|
|
| 22.04 LTS jammy | Not in release |
Severity score breakdown
CVSS version:
Base score
2.1 · Low
Vector: CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
Base score
2.2 · Low
Vector: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:L/A:N