{"id":"CVE-2026-42181","revision":"215de8e855f14b6eb53babc5f1027f57","records":[{"revision":"215de8e855f14b6eb53babc5f1027f57","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-42181","aliases":[],"title":"Lemmy: SSRF and internal image disclosure in post link metadata via unvalidated og:image","description":"Lemmy is a link aggregator and forum for the fediverse. Prior to version 0.19.18, Lemmy fetches metadata for user-supplied post URLs and, under the default StoreLinkPreviews image mode, downloads the preview image through local pict-rs. While the top-level page URL is checked against internal IP ranges, the extracted og:image URL is not subject to the same restriction. As a result, an authenticated low-privileged user can submit an attacker-controlled public page whose Open Graph image points to an internal image endpoint. Lemmy will fetch that internal image server-side and store a local thumbnail that can then be served back to users. This issue has been patched in version 0.19.18.","state":0,"publishedAt":"2026-05-08T19:26:07.763+00:00","modifiedAt":"2026-05-11T16:01:01.124+00:00","affected":[{"ecosystem":"Vendor product","name":"lemmy","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"LemmyNet\",\n                    \"product\": \"lemmy\",\n                    \"versions\": [\n                        {\n                            \"version\": \"< 0.19.18\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N","score":6.5,"severity":"MEDIUM"}],"references":["https://github.com/LemmyNet/lemmy/security/advisories/GHSA-h6hf-9846-xwrq","https://github.com/LemmyNet/lemmy/releases/tag/0.19.18"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-42181","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-42181","identifiers":["CVE-2026-42181"]},"retained":false,"historicalAffected":[]}],"coverage":[]}