{"id":"EUVD-2026-28820","enisaUuid":"8d63f445-f86b-3b9b-9cb8-6737a46126d2","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.","datePublished":"May 8, 2026, 7:26:07 PM","dateUpdated":"May 11, 2026, 4:01:01 PM","baseScore":6.5,"baseScoreVersion":"3.1","baseScoreVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N","references":"https://github.com/LemmyNet/lemmy/security/advisories/GHSA-h6hf-9846-xwrq\nhttps://github.com/LemmyNet/lemmy/releases/tag/0.19.18\n","aliases":"CVE-2026-42181\n","assigner":"GitHub_M","epss":0.26,"enisaIdProduct":[{"id":"92b79f96-b7d5-3cfb-a02f-c19a7fce5da1","product":{"name":"lemmy","vendor":{"name":"LemmyNet"}},"product_version":"\u003c 0.19.18"}],"enisaIdVendor":[{"id":"737b4e38-bc3f-37f9-8085-453ea487a6ae","vendor":{"name":"LemmyNet"}}],"enisaIdVulnerability":[{"id":"7c93e065-7393-3799-8ce1-bb796cbd45e2","vulnerability":{"id":"CVE-2026-42181","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.","datePublished":"May 8, 2026, 7:26:07 PM","dateUpdated":"May 11, 2026, 4:01:01 PM","status":"PUBLISHED","baseScore":6.5,"baseScoreVersion":"3.1","baseScoreVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N","references":"https://github.com/LemmyNet/lemmy/security/advisories/GHSA-h6hf-9846-xwrq\nhttps://github.com/LemmyNet/lemmy/releases/tag/0.19.18\n","enisa_id":"EUVD-2026-28820\n","assigner":"GitHub_M","epss":0.26,"dataProcessed":"Nov 7, 2026, 7:21:17 AM","vulnerabilityProduct":[{"id":"20767cf0-5dc9-32fb-9f20-62778632f9c2","product":{"name":"lemmy","vendor":{"name":"LemmyNet"}},"product_version":"\u003c 0.19.18"}],"vulnerabilityVendor":[{"id":"75cd2ed0-00e6-362e-8526-d5ad2f71ad70","vendor":{"name":"LemmyNet"}}]}}],"enisaIdAdvisory":[]}