Buffer overflow in mg_resolve_from_hosts_file in Mongoose 6.18, when reading from a crafted hosts file.
Priority HIGH 73CWE-120Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- Required
- 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-120 and the CVSS impact.
Summary
Buffer overflow in mg_resolve_from_hosts_file in Mongoose 6.18, when reading from a crafted hosts file.
Why it matters now
Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00703 53rd 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
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- No
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
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-2020-25887
- 2026-10-03 Alias added: GHSA-mj7x-c9vq-67qh
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-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
- TI-2019-13923 An integer overflow in parse_mqtt in mongoose.c in Cesanta Mongoose 6.16 allows an… CVSS 3.1CRITICAL 9.8
Sources
- CVE-2020-25887 · CVE Program
- CVE-2020-25887 · NVD
- FIRST EPSS
- GHSA-mj7x-c9vq-67qh · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences