CVE Explorer
CVE-2026-33131
H3 is a minimal H(TTP) framework. Versions 2.0.0-0 through 2.0.1-rc.14 contain a Host header spoofing vulnerability in the NodeRequestUrl (which extends FastURL) which allows middleware bypass. When event.url, event.url.hostname, or event.url._url is accessed, such as in a logging middleware, the _url getter constructs a URL from untrusted data, including the user-controlled Host header. Because H3's router resolves the route handler before middleware runs, an attacker can supply a crafted Host
Known exploited
Not asserted
Disputed
No
Stale source
No
Conflicts
0
Affected products and versions
1 source assertion{"product":"h3","vendor":"h3js","versions":[{"status":"affected","version":">= 2.0.0-0, < 2.0.1-rc.15"}]}
- cve_program_cvelist_v5affectedurn:baitaphish:normalized-source-record:v2:75a38ee26f262ce9deb2c106c35814172bdad878dd3c11696c5ae1a53efae15a · sha256:796e4e52861bd0b7… · /containers/cna/affected/0
Provider-owned CVSS observations
1 source assertion{"metric":{"attackComplexity":"HIGH","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":7.4,"baseSeverity":"HIGH","confidentialityImpact":"HIGH","integrityImpact":"HIGH","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","version":"3.1"},"metric_type":"cvssV3_1"}
- cve_program_cvelist_v5cvssurn:baitaphish:normalized-source-record:v2:75a38ee26f262ce9deb2c106c35814172bdad878dd3c11696c5ae1a53efae15a · sha256:796e4e52861bd0b7… · /containers/cna/metrics/0/cvssV3_1
CWE assertions
1 source assertion{"cweId":"CWE-290","description":"CWE-290: Authentication Bypass by Spoofing","lang":"en","type":"CWE"}
- cve_program_cvelist_v5cweurn:baitaphish:normalized-source-record:v2:75a38ee26f262ce9deb2c106c35814172bdad878dd3c11696c5ae1a53efae15a · sha256:796e4e52861bd0b7… · /containers/cna/problemTypes/0/descriptions/0
Source references
1 source assertion{"name":"https://github.com/h3js/h3/security/advisories/GHSA-3vj8-jmxq-cgj5","tags":["x_refsource_CONFIRM"],"url":"https://github.com/h3js/h3/security/advisories/GHSA-3vj8-jmxq-cgj5"}
- cve_program_cvelist_v5referenceurn:baitaphish:normalized-source-record:v2:75a38ee26f262ce9deb2c106c35814172bdad878dd3c11696c5ae1a53efae15a · sha256:796e4e52861bd0b7… · /containers/cna/references/0
Attribution and limitations
- CVE Program CVEList V5: Reproduce the MITRE copyright designation and CVE license in copies. Source →
Provider severity values are preserved separately. Baitaphish does not convert them into a risk rating, infer affected products, or treat EPSS as observed exploitation.