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.
Published: 2026-04-25
Score: 6.9 Medium
EPSS: n/a
KEV: No
Impact: n/a
Action: n/a
AI Analysis

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Remediation

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Tracking

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Advisories

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History

Sat, 25 Apr 2026 16:30:00 +0000

Type Values Removed Values Added
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.
Title Cesanta Mongoose TCP Option net_builtin.c handle_opt infinite loop
First Time appeared Cesanta
Cesanta mongoose
Weaknesses CWE-404
CWE-835
CPEs cpe:2.3:a:cesanta:mongoose:*:*:*:*:*:*:*:*
Vendors & Products Cesanta
Cesanta mongoose
References
Metrics cvssV2_0

{'score': 5, 'vector': 'AV:N/AC:L/Au:N/C:N/I:N/A:P/E:POC/RL:OF/RC:C'}

cvssV3_0

{'score': 5.3, 'vector': 'CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L/E:P/RL:O/RC:C'}

cvssV3_1

{'score': 5.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L/E:P/RL:O/RC:C'}

cvssV4_0

{'score': 6.9, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P'}

Subscriptions

Cesanta Mongoose
cve-icon MITRE

Status: PUBLISHED

Assigner: VulDB

Published:

Updated: 2026-04-25T16:15:13.639Z

Reserved: 2026-04-24T19:12:47.755Z

Link: CVE-2026-6985

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-04-25T17:16:33.520

Modified: 2026-04-25T17:16:33.520

Link: CVE-2026-6985

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.

Weaknesses