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TI-2017-02111 Aliases CVE-2017-2891GHSA-rwjm-353c-64rx

Use after free in Cesanta Mongoose

Priority MEDIUM 47CWE-416Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-416 and the CVSS impact.

Summary

An exploitable use-after-free vulnerability exists in the HTTP server implementation of Cesanta Mongoose 6.8. An ordinary HTTP POST request with a CGI target can cause a reuse of previously freed pointer potentially resulting in remote code execution. An attacker needs to send this HTTP request over the network to trigger this vulnerability.

Why it matters now

EPSS 0.0276 86th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
CesantaMongoose6.8—No fix listedCNA
  • Mongoose VendorCesanta Affected 6.8 Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:cesanta:mongoose:6.8:*:*:*:*:*:*:*6.8VulnerableCesanta
  • cpe:2.3:a:cesanta:mongoose:6.8:*:*:*:*:*:*:* Versions 6.8 Vulnerable ·Cesanta

Remediation

No fixed version listed by the sources yet.

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-02 Threatist record created from CVE-2017-2891
  2. 2026-10-03 Alias added: GHSA-rwjm-353c-64rx

References

Exploit 1

  • TI-2026-51393 Mongoose: Content-Length + Transfer-Encoding coexistence enables request smuggling CVSS 3.1CRITICAL 9.1
  • TI-2026-51389 Mongoose: TLS Hostname Verification Bypass via Overly Permissive Wildcard Matching CVSS 4.0CRITICAL 9.1
  • TI-2023-02723 Cesanta Mongoose MQTT Message Parsing Heap Overflow CVSS 3.1HIGH 8.8
  • TI-2020-15865 Buffer overflow in mg_resolve_from_hosts_file in Mongoose 6.18, when reading from a crafted hosts file. CVSS 3.1HIGH 8.8
  • TI-2023-17032 The HTTP server in Mongoose before 7.10 accepts requests containing negative… CVSS 3.1HIGH 7.5
  • TI-2026-06113 Cesanta Mongoose TCP Option net_builtin.c handle_opt infinite loop CVSS 4.0MEDIUM 6.9
See all 54 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences