CVE-2026-29975 (GCVE-0-2026-29975)

Vulnerability from cvelistv5 – Published: 2026-05-08 00:00 – Updated: 2026-05-08 18:07
VLAI
Summary
lwjson 1.8.1 contains an improper input validation vulnerability in the streaming JSON parser (lwjson_stream.c). The end-of-string detection logic incorrectly identifies escaped quote characters by only checking the immediately preceding character rather than counting consecutive backslashes, causing valid JSON strings ending with an escaped backslash (like "\\") to never terminate parsing. A remote attacker can send well-formed JSON to cause applications using lwjson_stream_parse() to hang indefinitely, resulting in denial of service.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-08 18:07 UTC
CWE
  • n/a
  • CWE-835 - Loop with Unreachable Exit Condition ('Infinite Loop')
Assigner
mitre CNA under the mitre root
CNA scorecard E 28/100 over 2362 records in the last 180 days details
References
Show details on NVD website
To clipboard 

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