CVE-2026-61520 (GCVE-0-2026-61520)
Vulnerability from cvelistv5 – Published: 2026-07-14 20:17 – Updated: 2026-07-28 01:49 X_Open Source
VLAI
EPSS
VEX
Title
Simple Machines Forum SSRF via image proxy
Summary
Simple Machines Forum 2.1 prior to commit 4bf35cf and 3.0 prior to commit b4d23df contains a server-side request forgery vulnerability in the image proxy that allows authenticated attackers to trigger internal HTTP requests by embedding attacker-controlled URLs in BBCode image tags, which the proxy fetches without validating resolved destination IPs against private address ranges, loopback, or link-local addresses. Attackers can leverage SMF's automatic HMAC signature generation for any embedded image URL to obtain valid signed proxy requests targeting internal services such as cloud instance metadata endpoints, internal web applications, and container network services.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-15 13:20 UTC
CWE
- CWE-918 - Server-Side Request Forgery (SSRF)
Assigner
References
3 references
| URL | Tags |
|---|---|
| https://github.com/SimpleMachines/SMF/commit/4bf3… | patch |
| https://github.com/SimpleMachines/SMF/commit/b4d2… | patch |
| https://www.vulncheck.com/advisories/simple-machi… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| SimpleMachines | SMF |
Affected:
2.1.0 , < 2.1.7
(semver)
Unaffected: 4bf35cf9e45573a5f55a6f52995086c1da89c096 (git) Unaffected: 3.0.0 (semver) Affected: b4d23dfd74a511587c605f9d294cefc3a75b4b26 (git) cpe:2.3:a:simplemachines:simple_machines_forum:*:*:*:*:*:*:*:* |
Date Public
2026-07-14 00:00
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