An invalid read of 8 bytes due to a use-after-free vulnerability in the…
Priority MEDIUM 48CWE-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 3.0 · NVD. Fix status from CNA. Impact type from CWE-416 and the CVSS impact.
Summary
An invalid read of 8 bytes due to a use-after-free vulnerability in the mg_http_free_proto_data_cgi function call in mongoose.c in Cesanta Mongoose Embedded Web Server Library 6.13 and earlier allows a denial of service (application crash) or remote code execution.
Why it matters now
EPSS 0.03574 89th 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
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | — | all versions | — | No fix listed | CNA |
- — Vendor— Affected all versions Fixed in — No fix listed CNA
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2018-20356
- 2026-10-03 Alias added: GHSA-2hwq-hrjc-wwr4
References
More Cesanta Mongoose vulnerabilities
- 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
Sources
- CVE-2018-20356 · CVE Program
- CVE-2018-20356 · NVD
- FIRST EPSS
- GHSA-2hwq-hrjc-wwr4 · GitHub Advisory Database · CC BY 4.0
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