CVE-2026-116734

flatcc through 0.6.4 contains an integer overflow vulnerability in the check_header function of the FlatBuffers verifier because its overflow guard is dead code. On 32-bit builds, attackers can supply a crafted buffer offset that wraps the bounds check, causing an out-of-bounds read before the buffer and crashing the process.

CVSS 4.0

6.3CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N

CVSS 3.1

3.7CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L

CWE

CWE-190

Published

2026-10-26

Modified

2026-10-26

Record from

the NVD, synced 2026-10-26

References

• https://github.com/dvidelabs/flatcc
• https://github.com/dvidelabs/flatcc/blob/v0.6.4/src/runtime/verifier.c#L126-L137
• https://github.com/dvidelabs/flatcc/commit/0df9c097a19badc8bd22d93af8fd47bd291e5d9f
• https://hackmd.io/@haindpwn/flatcc-json-number-oob-read
• https://www.vulncheck.com/advisories/flatcc-through-0.6.4-out-of-bounds-read-via-verifier-check-header

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