Integer overflow in Dvidelabs Flatcc
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.
Vulnerability class: Integer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 3.7 (Low). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- github.com/dvidelabs/flatcc/commit/0df9c097a19badc8bd22d93af8fd47bd291e5d9f (patch)
- github.com/dvidelabs/flatcc (product)
- github.com/dvidelabs/flatcc/blob/v0.6.4/src/runtime/verifier.c (technical-description)
- hackmd.io/@haindpwn/flatcc-json-number-oob-read (third-party-advisory)
- www.vulncheck.com/advisories/flatcc-through-0.6.4-out-of-bounds-read-via-verifi… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-116734?
- CVE-2026-116734 is a low-severity vulnerability in Dvidelabs Flatcc, classified under Integer Overflow or Wraparound. CVSS score: 3.7/10. Published 2026-10-26.
- How severe is CVE-2026-116734?
- Low severity. CVSS v3 base score is 3.7 out of 10.