SARA / Free Tools / CVE / CVE-2023-41337

CVE-2023-41337 — h2o is an HTTP server with support for HTTP/1

h2o is an HTTP server with support for HTTP/1.x, HTTP/2 and HTTP/3. In version 2.3.0-beta2 and prior, when h2o is configured to listen to multiple addresses or ports with each of them using different backend servers managed by multiple entities, a malicious backend entity that al

CVSS
6.1 MEDIUM
EPSS
8.00% (top 76.30%)
CWE
CWE-347
Published
2023-12-12T19:42:35.210Z
Last modified
2024-08-02T19:01:34.582Z
CVSS vector
CVSS:3.1/AV:A/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:N

01What is this vulnerability?

h2o is an HTTP server with support for HTTP/1.x, HTTP/2 and HTTP/3. In version 2.3.0-beta2 and prior, when h2o is configured to listen to multiple addresses or ports with each of them using different backend servers managed by multiple entities, a malicious backend entity that also has the opportunity to observe or inject packets exchanged between the client and h2o may misdirect HTTPS requests…

02Affected products

VendorProductVersions
h2oh2o<= 2.3.0-beta2

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Open the Sigma generator with a pre-filled prompt for this CVE to draft a starting detection in your stack of choice:

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07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

09References

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