CVE-2026-32239 (GCVE-0-2026-32239)

Vulnerability from cvelistv5 – Published: 2026-03-12 19:33 – Updated: 2026-03-13 16:15
VLAI
Title
Cap'n Proto has an integer overflow in KJ-HTTP
Summary
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.
Severity
6.3 (Medium)
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-13 16:14 UTC
CWE
  • CWE-444 - Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')
  • CWE-190 - Integer Overflow or Wraparound
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 8083 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
capnproto capnproto Affected: < 1.4.0
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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