{"id":"CVE-2026-100863","published":"2026-09-27T02:17:26.117","lastModified":"2026-09-28T20:57:50.143","description":"Heym versions 0.0.90 and earlier contain two server-side request forgery (SSRF) egress gaps, both remediated in app/services/ssrf_guard.py in 0.0.91. First, the LLM image-edit input loader (_load_image_bytes) fetched caller-controlled HTTP/HTTPS URLs with a bare httpx.get, applying only a scheme check and bypassing the egress-pinning HTTP client; because the workflow DSL supports \"imageInput\": \"$userInput.body.imageUrl\", a webhook or API caller can choose the fetch target when a workflow author uses that expression, allowing requests to loopback, RFC1918, and cloud metadata endpoints. Second, _is_public_address unwrapped only IPv4-mapped IPv6 addresses, so IPv6 transition forms — the NAT64 well-known prefix 64:ff9b::/96, deprecated IPv4-compatible ::x.x.x.x addresses, and 6to4 (2002::/16, classified as globally routable by Python 3.11.0 through 3.11.9) — could carry loopback, RFC1918, link-local, or cloud-metadata IPv4 destinations past both the initial URL validation and the dial-time IP pin. Version 0.0.91 routes the image loader through guard_http_url and the guarded client, evaluates NAT64 and IPv4-compatible addresses by their embedded IPv4 address, and refuses 64:ff9b:1::/48, 6to4, and Teredo (2001::/32) outright.","cvssScore":5,"cvssSeverity":"MEDIUM","cvssVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N","cwes":["CWE-918"],"vendors":[],"products":[],"references":[{"url":"https://github.com/heymrun/heym/security/advisories/GHSA-6rph-qqcv-jqh4","tags":[]},{"url":"https://www.vulncheck.com/advisories/heym-before-0.0.91-ssrf-via-image-fetching-and-ipv6-validation","tags":[]}],"exploitRefs":[{"url":"https://github.com/heymrun/heym/security/advisories/GHSA-6rph-qqcv-jqh4","tags":[]}],"hasPoc":true,"ai":null}