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 v3 3.7 LOW

3.7^/10

CVSS v3 : LOW

Vector :

Exploitability : 2.2 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
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

Configurations

No configuration.

History

26 Oct 2026, 22:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-26 22:16

Updated : 2026-10-27 15:16

NVD link : CVE-2026-116734

Mitre link : CVE-2026-116734

CVE.ORG link : CVE-2026-116734

JSON object : View

Products Affected

No product.

CWE

CWE-190

Integer Overflow or Wraparound

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