CVE-2026-116733

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.

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/json_parser.c#L539-L543
https://github.com/dvidelabs/flatcc/commit/356792dc155a9e685acdfe0ec1e209bdadcb4ab9
https://hackmd.io/@haindpwn/flatcc-json-number-oob-read
https://www.vulncheck.com/advisories/flatcc-through-0.6.4-out-of-bounds-read-via-flatcc-json-parser-number

Configurations

No configuration.

History

26 Oct 2026, 22:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-26 22:16

Updated : 2026-10-26 22:16

NVD link : CVE-2026-116733

Mitre link : CVE-2026-116733

CVE.ORG link : CVE-2026-116733

JSON object : View

Products Affected

No product.

CWE

CWE-125

Out-of-bounds Read

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