Bug 2559964 - CVE-2026-93601 maturin: rustls-webpki: Name Constraint Bypass in wildcard certificate validation [fedora-all]
Summary: CVE-2026-93601 maturin: rustls-webpki: Name Constraint Bypass in wildcard cer...
Keywords:
Status: CLOSED NOTABUG
Alias: None
Product: Fedora
Classification: Fedora
Component: maturin
Version: rawhide
Hardware: Unspecified
OS: Unspecified
low
low
Target Milestone: ---
Assignee: Fabio Valentini
QA Contact:
URL:
Whiteboard: {"flaws": ["94568926-7455-4c8f-8f71-6...
Depends On:
Blocks: CVE-2026-93601
TreeView+ depends on / blocked
 
Reported: 2026-10-23 15:49 UTC by Ronit Dey
Modified: 2026-10-23 20:48 UTC (History)
4 users (show)

Fixed In Version:
Clone Of:
Environment:
Last Closed: 2026-10-23 20:48:10 UTC
Type: ---
Embargoed:


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Description Ronit Dey 2026-10-23 15:49:38 UTC
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.

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.

Comment 1 Ben Beasley 2026-10-23 20:48:10 UTC
While rustls-webpki is in the upstrem Cargo.lock file, maturin as we build it doesn’t use that crate. This can be proved by looking at the LICENSE.dependencies file.

(We’ve also had rust-rustls-webpki at 0.103.12 or later for about six months. All maturin branches have been rebuilt and had updates issued since then except for EPEL10.2.)


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