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.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| rustls | webpki | 0.101.0 – < 0.103.12, 0.104.0-alpha.1 – < 0.104.0-alpha.6 | 0.103.12 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | rust-rustls-webpki | 0.103.13+ds-1 | — |
| Debian 13 | rust-rustls-webpki | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.04 LTS | rust-rustls-webpki | No fix yet | — |
| Ubuntu 24.04 LTS | rust-rustls-webpki | No fix yet | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | aws-nitro-enclaves-cli | 1.5.2~git0.1c496ed-150600.10.18.1 | SUSE-SU-2026:5066-1 |
| SLES 15 SP6 | aws-nitro-enclaves-cli | 1.5.2~git0.1c496ed-150600.10.18.1 | SUSE-SU-2026:5066-1 |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 16.0 | aws-nitro-enclaves-cli | 1.5.2~git0.1c496ed-160000.1.1 | SUSE-SU-2026:24467-1 |
| SLES for SAP 16.0 | rustup | 1.29.1~0-160000.1.1 | SUSE-SU-2026:24014-1 |
| SLES for SAP 16.0 | sccache | 0.18.0~2-160000.1.1 | SUSE-SU-2026:23983-1 |
| SLES 16.0 | aws-nitro-enclaves-cli | 1.5.2~git0.1c496ed-160000.1.1 | SUSE-SU-2026:24467-1 |
| SLES 16.0 | rustup | 1.29.1~0-160000.1.1 | SUSE-SU-2026:24014-1 |
| SLES 16.0 | sccache | 0.18.0~2-160000.1.1 | SUSE-SU-2026:23983-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | python-tokenizers | 0.23.2-1.1 | openSUSE-SU-2026:11936-1 |
| openSUSE Leap 16.0 | aws-nitro-enclaves-cli | 1.5.2~git0.1c496ed-160000.1.1 | openSUSE-SU-2026:22175-1 |
| openSUSE Leap 16.0 | rustup | 1.29.1~0-160000.1.1 | openSUSE-SU-2026:22016-1 |
| openSUSE Leap 16.0 | sccache | 0.18.0~2-160000.1.1 | openSUSE-SU-2026:21982-1 |
| openSUSE Leap 16.0 | sequoia-sq | 1.5.0-bp160.1.1 | openSUSE-RU-2026:22132-1 |
| openSUSE Leap 16.0 | shadowsocks-libev | 3.3.6-bp160.3.1 | openSUSE-SU-2026:22189-1 |
| openSUSE Leap 16.0 | shadowsocks-rust | 1.25.0-bp160.1.1 | openSUSE-SU-2026:22189-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | amazon-efs-utils | 3.3.5-1.amzn2023 | ALAS2023-2026-3378 |
| Amazon Linux 2023 | aws-workload-credentials-provider | 3.1.2-1.amzn2023 | ALAS2023-2026-3375 |
| Amazon Linux 2 | amazon-efs-utils | 3.3.5-1.amzn2 | ALAS2-2026-4069 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | kata-containers-cc | 3.15.0.aks0-23 | — |
| Azure Linux 3 | rust +1 | No fix yet | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| crates.io | rustls-webpki | >= 0.101.0, < 0.103.12 | 0.103.12 | GHSA-xgp8-3hg3-c2mh |
| crates.io | rustls-webpki | >= 0.104.0-alpha.1, < 0.104.0-alpha.6 | 0.104.0-alpha.6 | GHSA-xgp8-3hg3-c2mh |
| crates.io | rustls-webpki | >= 0.0.0-0, < 0.103.12 · >= 0.104.0-alpha.1, < 0.104.0-alpha.6 | 0.103.12, 0.104.0-alpha.6 | RUSTSEC-2026-0099 |
Advisories 13
- ALAS2023-2026-3375 Important: aws-workload-credentials-provider security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Nov 9, 2026
- ALAS2023-2026-3378 Important: amazon-efs-utils security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Nov 9, 2026
- ALAS2-2026-4069 Important: amazon-efs-utils security update (Amazon Linux 2) Amazon Linux Security Center (ALAS) · Nov 9, 2026
- SUSE-SU-2026:24467-1 Security update for aws-nitro-enclaves-cli SUSE / openSUSE Security Updates · Nov 4, 2026
- SUSE-SU-2026:5066-1 Security update for aws-nitro-enclaves-cli SUSE / openSUSE Security Updates · Nov 3, 2026
- openSUSE-SU-2026:22175-1 Security update for aws-nitro-enclaves-cli SUSE / openSUSE Security Updates · Nov 1, 2026
- openSUSE-SU-2026:22189-1 Security update for shadowsocks-rust, shadowsocks-libev SUSE / openSUSE Security Updates · Nov 1, 2026
- openSUSE-RU-2026:22132-1 Recommended update for sequoia-sq SUSE / openSUSE Security Updates · Oct 20, 2026
- SUSE-SU-2026:24014-1 Security update for rustup SUSE / openSUSE Security Updates · Oct 9, 2026
- SUSE-SU-2026:23983-1 Security update for sccache SUSE / openSUSE Security Updates · Oct 6, 2026
- openSUSE-SU-2026:22016-1 Security update for rustup SUSE / openSUSE Security Updates · Oct 3, 2026
- openSUSE-SU-2026:21982-1 Security update for sccache SUSE / openSUSE Security Updates · Oct 1, 2026
- openSUSE-SU-2026:11936-1 python313-tokenizers-0.23.2-1.1 on GA media SUSE / openSUSE Security Updates · Oct 1, 2026
References
- GitHub Security Advisory (GHSA-xgp8-3hg3-c2mh) vendor-advisory
- VulnCheck Advisory: rustls webpki 0.101.0 before 0.103.12 Name Constraint Bypass third-party-advisory