CVE-2026-90785

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.

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.

An out-of-bounds read vulnerability exists in the schema lexer of flatcc 4c3b999e. When an exact-length FlatBuffers schema ends with an unterminated quotation mark, the C-string scanning logic in lex() dereferences the input pointer after it has reached the end of the buffer. A specially crafted schema can trigger a one-byte heap buffer over-read, resulting in application crash and denial of service.

An out-of-bounds read vulnerability exists in the schema lexer of flatcc 4c3b999e. When an exact-length FlatBuffers schema buffer ends with a digit, the integer digit-scan loop in lex() advances past the end of the input buffer and dereferences the out-of-bounds pointer. A specially crafted schema can trigger a one-byte heap buffer over-read, resulting in application crash and denial of service.

A vulnerability was determined in Dvidelabs flatcc up to 0.6.3. This impacts the function align_order_members of the file src/compiler/semantics.c of the component Duplicate Symbol Handler. This manipulation causes reachable assertion. The attack can be initiated remotely. The exploit has been publicly disclosed and may be utilized. Patch name: 8b19ba4e992ebcad7f5970704d1afc5507fa5205. To fix this issue, it is recommended to deploy a patch.

A vulnerability has been found in Dvidelabs flatcc up to 0.6.3. The impacted element is the function fb_clear_parser of the file src/Compiler/semantics.c. The manipulation leads to memory leak. It is possible to initiate the attack remotely. The exploit has been disclosed to the public and may be used. The identifier of the patch is 8dbc3419738da066151991fd2bf1d0c85591dea2. It is suggested to install a patch to address this issue.