CVE-2026-53622: Traefik: HTTP/3 mTLS bypass via exact SNI TLSOptions lookup for wildcard and mixed-case hosts
Noroxi assessment
Priority: Monitor (action score 31/100)
- The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
- Probability of exploitation in the next 30 days: 0.62% (FIRST EPSS); higher than 50.1% of all records.
- Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
- According to CISA the attack is automatable: targets can be found by mass scanning.
- Fixed version: github.com/traefik/traefik/v2 (Go) 2.11.51; github.com/traefik/traefik/v3 (Go) 3.7.3, 3.6.18; traefik (openSUSE:Tumbleweed) 3.7.5-1.1.
- Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).
Low priority for now. Upgrade to github.com/traefik/traefik/v2 (Go) 2.11.51; github.com/traefik/traefik/v3 (Go) 3.7.3, 3.6.18; traefik (openSUSE:Tumbleweed) 3.7.5-1.1 or later.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
Primary sources: NVD · CVE.org · FIRST EPSS
Traefik is an HTTP reverse proxy and load balancer. Versions prior to 3.7.3, 3.6.18, and 2.11.51 have a critical vulnerability in Traefik's HTTP/3 (QUIC) TLS configuration selection that allows unauthenticated clients to bypass router-specific mTLS enforcement. When HTTP/3 is enabled on an entrypoint, the TLS handshake selects the applicable TLS configuration through an exact, case-sensitive lookup on the SNI value, which fails to match wildcard host patterns (e.g., *.example.com) or case variants of the configured hostname. Because the handshake falls back to the default TLS configuration — which may not require client certificates — a client can complete the QUIC handshake without presenting a certificate, while the subsequent HTTP routing layer still dispatches the request to a backend protected by a router-specific mTLS policy. The issue affects deployments where HTTP/3 is enabled, a router uses a wildcard Host rule or case-insensitive hostname matching, a router-specific TLSOptions enforces client certificate authentication, and UDP access to the entrypoint is reachable by an attacker. This vulnerability is fixed in versions 3.7.3, 3.6.18, and 2.11.51.
- Published
- Jun 23, 2026
- Updated
- Sep 2, 2026
- EPSS
- 0.6% · 50th percentile
- CWE
- CWE-288
Report tools
Action score
31
Monitor
Low priority for now.
- CVSS
- 31 / 40 · 7.8 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.6%
CISA SSVC decision
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- —
- CNA · GitHub_M
- 7.8
- NVD has not scored this yet; the score shown is the CNA’s.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- A fix has been released
If any of these changes, we'll tell you in the daily email digest.
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Noroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
| Vendor | Product | CPE |
|---|---|---|
| traefik | traefik | cpe:2.3:a:traefik:traefik |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- traefik traefikbefore 3.7.3
Versions reported by the vendor
Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.
traefik traefik
- >= 3.7.0, < 3.7.3, >= 3.0.0, < 3.6.18, < 2.11.51affected
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Go | github.com/traefik/traefik | from 0 | — |
| Go | github.com/traefik/traefik | up to and including 1.7.34 | — |
| Go | github.com/traefik/traefik/v2 | before 2.11.51 | 2.11.51 |
| Go | github.com/traefik/traefik/v3 | from 3.7.0 · before 3.7.3 | 3.7.3 |
| Go | github.com/traefik/traefik/v3 | before 3.6.18 | 3.6.18 |
| Go | github.com/traefik/traefik/v3 | before 3.7.3 | 3.7.3 |
| openSUSE:Tumbleweed | traefik | before 3.7.5-1.1 | 3.7.5-1.1 |
Same product
traefik: all recordsOther highest-scoring records for the same primary product.
- CVE-2026-85595Traefik before v2.11.55 and v3.0.0 through v3.7.10 Authentication Bypass via digestAuth38Monitor
- CVE-2026-88877Traefik v3.7.0 Authentication Bypass via from-to-www-redirect37Monitor
- CVE-2026-88007Traefik HTTP/3 Backend NTLM Connection Reuse36Monitor
Published before and after this one in the same product
- ← EarlierCVE-2026-48020Jun 23, 2026 · Traefik StripPrefix Route-Level Auth Bypass via Path Normalization31Monitor
- ← EarlierCVE-2026-48491Jun 23, 2026 · Traefik: SNICheck ignores wildcard TLSOptions mappings, allowing domain-fronted mTLS bypass31Monitor
- Later →CVE-2026-54761Jun 23, 2026 · Traefik: Kubernetes Gateway crossProviderNamespaces bypass allows HTTPRoute outside the allowlist to expose internal Traefik services24Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| Go:github.com/traefik/traefik/v2 | 2.11.51 | Package registry (OSV) |
| Go:github.com/traefik/traefik/v3 | 3.6.18 | Package registry (OSV) |
| Go:github.com/traefik/traefik/v3 | 3.7.3 | Package registry (OSV) |
| opensuse:traefik | 3.7.5-1.1 · openSUSE:Tumbleweed | Package registry (OSV) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
No history yet (it accumulates with the daily EPSS job).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
- CVE-2026-480200 days apartTraefik StripPrefix Route-Level Auth Bypass via Path Normalization31Monitor
- CVE-2026-484910 days apartTraefik: SNICheck ignores wildcard TLSOptions mappings, allowing domain-fronted mTLS bypass31Monitor
- CVE-2026-114635121 days apartTraefik before v2.11.58 and v3.7.14 SNI Check Bypass via HTTP/2 Scheme28Monitor
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
National notice (Türkiye Cybersecurity Directorate / USOM)
Official security notices citing this record; remediation advice is on the agency's page.
- TR-26-0438 · Jun 24, 2026(Traefik Proxy Güvenlik Zafiyeti)
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- No account or password is required.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- Integrity
- Availability
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- X
Weakness class (CWE)
CWE-288 · Authentication Bypass Using an Alternate Path or ChannelCVSS vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
nvd-secondary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
Change log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (7 more)Show less
- bugzilla.redhat.com/show_bug.cgi?id=2491924
- community.traefik.io/t/new-security-update-for-traefik-2-11-2-11-48-3-6-3-6-19-and-3-7-3-7-3/29917
- github.com/traefik/traefik/compare/v3.6.17...v3.6.18
- github.com/traefik/traefik/pull/13214
- github.com/traefik/traefik/releases/tag/v3.7.3
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-53622.json
- access.redhat.com/errata/RHSA-2026:62260
Vendor advisories and official records. Exploit/PoC links are deliberately left out.