Vulnerability Description
A weakness has been identified in Cesanta Mongoose up to 7.20. This vulnerability affects the function handle_opt of the file /src/net_builtin.c of the component TCP Option Handler. This manipulation of the argument optlen causes infinite loop. The attack is possible to be carried out remotely. The exploit has been made available to the public and could be used for attacks. Upgrading to version 7.21 is able to resolve this issue. Upgrading the affected component is advised. VulDB has contacted the vendor early and they confirmed quickly, that this issue got fixed already.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Cesanta | Mongoose | >= 7.0, < 7.21 |
Related Weaknesses (CWE)
References
- https://github.com/cesanta/mongoose/releases/tag/7.21ProductRelease Notes
- https://github.com/dwBruijn/CVEs/blob/main/Mongoose/TCP_opt_dos.mdExploitThird Party Advisory
- https://vuldb.com/submit/796230Third Party AdvisoryVDB Entry
- https://vuldb.com/vuln/359528Third Party AdvisoryVDB Entry
- https://vuldb.com/vuln/359528/ctiPermissions RequiredVDB Entry
FAQ
What is CVE-2026-6985?
CVE-2026-6985 is a vulnerability with a CVSS score of 5.3 (MEDIUM). A weakness has been identified in Cesanta Mongoose up to 7.20. This vulnerability affects the function handle_opt of the file /src/net_builtin.c of the component TCP Option Handler. This manipulation ...
How severe is CVE-2026-6985?
CVE-2026-6985 has been rated MEDIUM with a CVSS base score of 5.3/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-6985?
Check the references section above for vendor advisories and patch information. Affected products include: Cesanta Mongoose.