Vulnerability · Published Oct 26, 2026 · Assigned by VulnCheck
CVE-2026-116733flatcc through 0.6.4 Out-of-Bounds Read via __flatcc_json_parser_number
Low 3.7
In plain English
A low-severity out-of-bounds read in flatcc from dvidelabs. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 37% of all known vulnerabilities).
Severity (CVSS 3.1)3.7Low
Exploit odds (30 days)0.4%top 63.4% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known
Official description
flatcc through 0.6.4 contains an out-of-bounds read vulnerability in __flatcc_json_parser_number that allows attackers to read past the input buffer via numbers ending in a decimal point. Attackers can supply untrusted JSON ending immediately after a decimal point to generated parsers, crashing applications when the buffer ends at an unmapped page.
Affected products (as reported)
Weakness: CWE-125 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
References
- Patch Commit patch
- https://github.com/dvidelabs/flatcc product
- https://github.com/dvidelabs/flatcc/blob/v0.6.4/src/runtime/json_parser.c#L539-L543 technical-description
- https://hackmd.io/@haindpwn/flatcc-json-number-oob-read third-party-advisory
- VulnCheck Advisory: flatcc through 0.6.4 Out-of-Bounds Read via __flatcc_json_parser_number third-party-advisory
- https://hackmd.io/@haindpwn/cve-2026-116733-116734-flatcc-json-number-oob-read exploit