# CVE-2026-90784: Dvidelabs flatcc memory leak in fb_clear_parser

Source: https://junglewise.ai/threats/cve-2026-90784-dvidelabs-flatcc-memory-leak-in-fb-clear-parser  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-14. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-90784 · Severity: medium · CVSS 5.3 · Published 2026-09-14

flatcc is a FlatBuffers compiler and C library used for serializing and deserializing data structures efficiently. A memory leak exists in the parser cleanup function where the keyword table is not deallocated, potentially causing memory to accumulate over time when processing multiple schema files. This can degrade performance or exhaust available memory in long-running compilation processes.

Technologies: [Dvidelabs Flatcc](https://junglewise.ai/threats/technologies/flatcc). Vendors: [Dvidelabs](https://junglewise.ai/threats/vendors/dvidelabs).

## Quick answers

**Is CVE-2026-90784 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-90784 being exploited in the wild.

**How severe is CVE-2026-90784?** Medium severity, with a CVSS score of 5.3, published 14 September 2026.

**Which products and versions are affected?** Dvidelabs Flatcc up to 0.6.3.

**Is there a fix for CVE-2026-90784?** A patch was published on 2026-09-14: Commit 8dbc3419738da066151991fd2bf1d0c85591dea2 addresses the issue Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-90784 attacked?** It is attacked over the network.

**Am I affected by CVE-2026-90784?** Check whether you run Dvidelabs Flatcc at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability is a memory leak in the fb_clear_parser function within src/compiler/parser.c. When the parser is cleared after processing a schema, the keyword_index table is not properly deallocated, only the include_index and attribute_index tables are freed. The fix adds a single call to fb_name_table_clear for the keyword_index. The vulnerability can be triggered remotely if the affected version is deployed as a compilation service, and requires no authentication. An attacker can repeatedly trigger schema compilation to accumulate memory leaks.

## Affected products

- Dvidelabs flatcc up to 0.6.3

## Timeline

- 2026-09-14: disclosed
- 2026-09-14: patched: Commit 8dbc3419738da066151991fd2bf1d0c85591dea2 addresses the issue

## References

- [https://github.com/dvidelabs/flatcc/](https://github.com/dvidelabs/flatcc/)
- [https://github.com/dvidelabs/flatcc/commit/8dbc3419738da066151991fd2bf1d0c85591dea2](https://github.com/dvidelabs/flatcc/commit/8dbc3419738da066151991fd2bf1d0c85591dea2)

## Related threats

- [flatcc schema lexer out-of-bounds read in string parsing](https://junglewise.ai/threats/cve-2026-88345-an-out-of-bounds-read-vulnerability-exists-in-the-schema-lexer-of)
- [flatcc schema lexer out-of-bounds read](https://junglewise.ai/threats/cve-2026-88344-an-out-of-bounds-read-vulnerability-exists-in-the-schema-lexer-of)
- [Dvidelabs flatcc reachable assertion in align_order_members](https://junglewise.ai/threats/cve-2026-90786-dvidelabs-flatcc-reachable-assertion-in-align-order-members)
- [Dvidelabs flatcc reachable assertion in struct analysis](https://junglewise.ai/threats/cve-2026-90785-dvidelabs-flatcc-reachable-assertion-in-struct-analysis)