CVE-2026-6985
Last modified
CVE-2026-6985 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. 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. EPSS estimates a 0.56% chance of exploitation in the next 30 days.
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.
Metrics
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Cesanta | Mongoose | >= 7.0, < 7.21 |
References
- https://github.com/cesanta/mongoose/releases/tag/7.21Product, Release Notes
- https://github.com/dwBruijn/CVEs/blob/main/Mongoose/TCP_opt_dos.mdExploit, Third Party Advisory
- https://vuldb.com/submit/796230Third Party Advisory, VDB Entry
- https://vuldb.com/vuln/359528Third Party Advisory, VDB Entry
- https://vuldb.com/vuln/359528/ctiPermissions Required, VDB Entry
Timeline
- Published
- Last Modified
- Status
- Analyzed
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How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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