CVE-2026-32239
mediumpriority · track · 26EPSS 0.002 · 11 %ileEUUSEPSS · scored 2026-10-22
Cap'n Proto is a data interchange format and capability-based RPC system. Prior to 1.4.0, a negative Content-Length value was converted to unsigned, treating it as an impossibly large length instead. In theory, this bug could enable HTTP request/response smuggling. This vulnerability is fixed in 1.4.0.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–medium · 1.7–6.5
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (2)
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 (16)
External citations — patches, advisories, analysis.
- https://capnproto.org/capnproto-c++-1.4.0.tar.gzcnnvd
- https://capnproto.org/capnproto-c++-win32-1.4.0.zipcnnvd
- https://github.com/capnproto/capnprotoPatchcnnvd
- https://github.com/capnproto/capnproto/commit/2744b3c012b4aa3c31cefb61ec656829fa5c0e36cnnvd
- https://github.com/capnproto/capnproto/commit/e929f0ba7901a6b8f4b5ba9a4db00af43288cbb0cnnvd
- https://github.com/capnproto/capnproto/security/advisories/GHSA-qjx3-pp3m-9jpmcnnvd
- https://capnproto.org/capnproto-c++-1.4.0.tar.gzenisa_euvd
- https://capnproto.org/capnproto-c++-win32-1.4.0.zipenisa_euvd
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