CVE-2023-30847
highpriority · track · 33EPSS 0.009 · 60 %ileEUUSEPSS · scored 2026-10-28
H2O is an HTTP server. In versions 2.3.0-beta2 and prior, when the reverse proxy handler tries to processes a certain type of invalid HTTP request, it tries to build an upstream URL by reading from uninitialized pointer. This behavior can lead to crashes or leak of information to back end HTTP servers. Pull request number 3229 fixes the issue. The pull request has been merged to the `master` branch in commit f010336. Users should upgrade to commit f010336 or later.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (3)
Products and version ranges known to be affected.
also known as (2)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (10)
External citations — patches, advisories, analysis.
- https://cxsecurity.com/cveshow/CVE-2023-30847/cnnvd
- https://github.com/h2o/h2o/commit/f010336bab162839df43d9e87570897466c97e33cnnvd
- https://github.com/h2o/h2o/pull/3229cnnvd
- https://github.com/h2o/h2o/security/advisories/GHSA-p5hj-phwj-hrvxcnnvd
- https://github.com/h2o/h2o/commit/f010336bab162839df43d9e87570897466c97e33enisa_euvd
- https://github.com/h2o/h2o/pull/3229enisa_euvd
- https://github.com/h2o/h2o/security/advisories/GHSA-p5hj-phwj-hrvxenisa_euvd
- https://github.com/h2o/h2o/commit/f010336bab162839df43d9e87570897466c97e33Patchnvd
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