{"id":"CVE-2026-39369","aliases":["EUVD-2026-19883","GHSA-f4f9-627c-jh33"],"status":"published","title":"WWBN AVideo's GIF poster fetch bypasses traversal scrubbing and exposes local files through public media URLs","description":"WWBN AVideo is an open source video platform. In versions 26.0 and prior, objects/aVideoEncoderReceiveImage.json.php allowed an authenticated uploader to fetch attacker-controlled same-origin /videos/... URLs, bypass traversal scrubbing, and expose server-local files through the GIF poster storage path. The vulnerable GIF branch could be abused to read local files such as /etc/passwd or application source files and republish those bytes through a normal public GIF media URL.","severity":{"version":"3.1","score":7.6,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:L","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.00428,"percentile":0.37326,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-22"],"published":"2026-04-07T19:24:33Z","modified":"2026-11-11T10:30:32Z","affected":[{"source":"ghsa","ecosystem":"Packagist","package":"WWBN/AVideo","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"26.0"}]}]},{"source":"osv","ecosystem":"Packagist","package":"WWBN/AVideo","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"26.0"}]}]}],"products":[{"vendor":"wwbn","product":"avideo"}],"references":[{"url":"https://github.com/WWBN/AVideo/security/advisories/GHSA-f4f9-627c-jh33","tags":["x_refsource_CONFIRM","Third Party Advisory","advisory","web"]},{"url":"https://github.com/WWBN/AVideo/commit/2375eb5e0a6d3cbcfb05377657d0820a7d470b1d","tags":["x_refsource_MISC","Patch","fix","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-39369","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-f4f9-627c-jh33"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/39xxx/CVE-2026-39369.json","tags":["advisory"]},{"url":"https://github.com/WWBN/AVideo","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2026-39369","title":"WWBN AVideo's GIF poster fetch bypasses traversal scrubbing and exposes local files through public media URLs","description":"WWBN AVideo is an open source video platform. In versions 26.0 and prior, objects/aVideoEncoderReceiveImage.json.php allowed an authenticated uploader to fetch attacker-controlled same-origin /videos/... URLs, bypass traversal scrubbing, and expose server-local files through the GIF poster storage path. The vulnerable GIF branch could be abused to read local files such as /etc/passwd or application source files and republish those bytes through a normal public GIF media URL.","status":"published","published":"2026-04-07T19:24:33.421Z","modified":"2026-05-14T16:05:11.967Z","cvss":[{"version":"3.1","score":7.6,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:L","level":"high","assessor":"cna"}],"cwes":["CWE-22"],"updated_at":"2026-11-02T14:20:02.662847Z"}],"euvd":[{"id":"EUVD-2026-19883","description":"WWBN AVideo is an open source video platform. In versions 26.0 and prior, objects/aVideoEncoderReceiveImage.json.php allowed an authenticated uploader to fetch attacker-controlled same-origin /videos/... URLs, bypass traversal scrubbing, and expose server-local files through the GIF poster storage path. The vulnerable GIF branch could be abused to read local files such as /etc/passwd or application source files and republish those bytes through a normal public GIF media URL.","status":"published","published":"2026-04-07T19:24:33Z","modified":"2026-05-14T16:05:11Z","cvss":[{"version":"3.1","score":7.6,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:L","level":"high"}],"updated_at":"2026-11-02T19:04:31.113278Z"}],"ghsa":[{"id":"GHSA-f4f9-627c-jh33","title":"WWBN AVideo's GIF poster fetch bypasses traversal scrubbing and exposes local files through public media URLs","description":"## Summary\n\n`objects/aVideoEncoderReceiveImage.json.php` allowed an authenticated uploader to fetch attacker-controlled same-origin `/videos/...` URLs, bypass traversal scrubbing, and expose server-local files through the GIF poster storage path.\n\nThe vulnerable GIF branch could be abused to read local files such as `/etc/passwd` or application source files and republish those bytes through a normal public GIF media URL.\n\n## Details\n\nThe vulnerable chain was:\n\n1. `objects/aVideoEncoderReceiveImage.json.php` accepted attacker-controlled `downloadURL_gifimage`\n2. traversal scrubbing used `str_replace('../', '', ...)`, which was bypassable with overlapping input such as `....//`\n3. same-origin `/videos/...` URLs were accepted\n4. `url_get_contents()` and `try_get_contents_from_local()` resolved the request into a local filesystem read\n5. the fetched bytes were written into the GIF destination\n6. invalid GIF cleanup used the wrong variable, so the non-image payload remained on disk\n\nThis made the GIF poster path a local file disclosure primitive with public retrieval.\n\n## Proof of concept\n\n1. Log in as an uploader and create an owned video row through the normal encoder flow.\n2. Send:\n\n```text\nPOST /objects/aVideoEncoderReceiveImage.json.php\ndownloadURL_gifimage=https://localhost/videos/....//....//....//....//....//....//etc/passwd\n```\n\n3. Query:\n\n```text\nGET /objects/videos.json.php?showAll=1\n```\n\n4. Recover the generated GIF URL from `videosURL.gif.url`.\n5. Download that GIF URL.\n6. Observe that the body matches the target local file, such as `/etc/passwd`, byte-for-byte.\n\n## Impact\n\nAn authenticated uploader can read server-local files and republish them through a public GIF media URL by supplying a crafted same-origin `/videos/...` path to `downloadURL_gifimage`. Because traversal scrubbing was bypassable and the fetched bytes were written to the GIF destination without effective invalid-image cleanup, successful exploitation allows disclosure of files such as `/etc/passwd`, readable application source code, or deployment-specific configuration accessible to the application.\n\n\n## Recommended fix\n\n- Reject any remote image URL whose decoded path contains traversal markers\n- Do not allow attacker-controlled same-origin `/videos/...` fetches to resolve into local file reads\n- Constrain any local shortcut path handling with `realpath()` and strict base-directory allowlists\n- Validate GIF content before saving it into public media storage\n- Ensure invalid-image cleanup checks the correct destination path","status":"published","published":"2026-04-08T00:08:44Z","modified":"2026-04-24T21:10:50Z","cvss":[{"version":"3.1","score":7.6,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:L","level":"high"}],"cwes":["CWE-22"],"updated_at":"2026-11-02T14:39:58.897998Z"}],"nvd":[{"id":"CVE-2026-39369","description":"WWBN AVideo is an open source video platform. In versions 26.0 and prior, objects/aVideoEncoderReceiveImage.json.php allowed an authenticated uploader to fetch attacker-controlled same-origin /videos/... URLs, bypass traversal scrubbing, and expose server-local files through the GIF poster storage path. The vulnerable GIF branch could be abused to read local files such as /etc/passwd or application source files and republish those bytes through a normal public GIF media URL.","status":"published","published":"2026-04-07T20:16:31.32Z","modified":"2026-07-24T21:10:00.143Z","cvss":[{"version":"3.1","score":7.6,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:L","level":"high","assessor":"secondary"}],"cwes":["CWE-22"],"updated_at":"2026-11-02T14:12:13.535987Z"}],"osv":[{"id":"CVE-2026-39369","title":"WWBN AVideo's GIF poster fetch bypasses traversal scrubbing and exposes local files through public media URLs","description":"WWBN AVideo is an open source video platform. In versions 26.0 and prior, objects/aVideoEncoderReceiveImage.json.php allowed an authenticated uploader to fetch attacker-controlled same-origin /videos/... URLs, bypass traversal scrubbing, and expose server-local files through the GIF poster storage path. The vulnerable GIF branch could be abused to read local files such as /etc/passwd or application source files and republish those bytes through a normal public GIF media URL.","status":"published","published":"2026-04-07T19:24:33.421Z","modified":"2026-11-11T10:30:32.837199505Z","cvss":[{"version":"3.1","score":7.6,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:L","level":"high"}],"cwes":["CWE-22"],"updated_at":"2026-11-11T11:06:44.829133Z"},{"id":"GHSA-f4f9-627c-jh33","title":"WWBN AVideo's GIF poster fetch bypasses traversal scrubbing and exposes local files through public media URLs","description":"## Summary\n\n`objects/aVideoEncoderReceiveImage.json.php` allowed an authenticated uploader to fetch attacker-controlled same-origin `/videos/...` URLs, bypass traversal scrubbing, and expose server-local files through the GIF poster storage path.\n\nThe vulnerable GIF branch could be abused to read local files such as `/etc/passwd` or application source files and republish those bytes through a normal public GIF media URL.\n\n## Details\n\nThe vulnerable chain was:\n\n1. `objects/aVideoEncoderReceiveImage.json.php` accepted attacker-controlled `downloadURL_gifimage`\n2. traversal scrubbing used `str_replace('../', '', ...)`, which was bypassable with overlapping input such as `....//`\n3. same-origin `/videos/...` URLs were accepted\n4. `url_get_contents()` and `try_get_contents_from_local()` resolved the request into a local filesystem read\n5. the fetched bytes were written into the GIF destination\n6. invalid GIF cleanup used the wrong variable, so the non-image payload remained on disk\n\nThis made the GIF poster path a local file disclosure primitive with public retrieval.\n\n## Proof of concept\n\n1. Log in as an uploader and create an owned video row through the normal encoder flow.\n2. Send:\n\n```text\nPOST /objects/aVideoEncoderReceiveImage.json.php\ndownloadURL_gifimage=https://localhost/videos/....//....//....//....//....//....//etc/passwd\n```\n\n3. Query:\n\n```text\nGET /objects/videos.json.php?showAll=1\n```\n\n4. Recover the generated GIF URL from `videosURL.gif.url`.\n5. Download that GIF URL.\n6. Observe that the body matches the target local file, such as `/etc/passwd`, byte-for-byte.\n\n## Impact\n\nAn authenticated uploader can read server-local files and republish them through a public GIF media URL by supplying a crafted same-origin `/videos/...` path to `downloadURL_gifimage`. Because traversal scrubbing was bypassable and the fetched bytes were written to the GIF destination without effective invalid-image cleanup, successful exploitation allows disclosure of files such as `/etc/passwd`, readable application source code, or deployment-specific configuration accessible to the application.\n\n\n## Recommended fix\n\n- Reject any remote image URL whose decoded path contains traversal markers\n- Do not allow attacker-controlled same-origin `/videos/...` fetches to resolve into local file reads\n- Constrain any local shortcut path handling with `realpath()` and strict base-directory allowlists\n- Validate GIF content before saving it into public media storage\n- Ensure invalid-image cleanup checks the correct destination path","status":"published","published":"2026-04-08T00:08:44Z","modified":"2026-09-10T03:50:44.094304555Z","cvss":[{"version":"3.1","score":7.6,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:L","level":"high"}],"cwes":["CWE-22"],"updated_at":"2026-11-02T15:46:46.006631Z"}]}}