CVE-2026-123206

Description

EdgeChat before 2.20.3 contains a missing authentication vulnerability in the GET /files/:key route that allows unauthenticated or banned users to download decrypted public-channel attachments because canAccessFile() accepts a null user id. Attackers holding an attachment object key can omit or supply an invalid token to retrieve plaintext attachments without a session or channel membership.

References

• https://github.com/aozorae/Edgechat/blob/1288c66997d5e2f9eefc515cf60b2072f8d655be/worker/src/data/uploaded-files.js#L146
• https://github.com/aozorae/Edgechat/commit/38cb5cf42d8014ca64624d4f4d565419b2fbeda9
• https://github.com/aozorae/Edgechat/issues/58
• https://hackmd.io/@hieund/edgechat-files-unauthenticated-public-attachment-disclosure
• https://www.vulncheck.com/advisories/edgechat-before-2.20.3-missing-authentication-for-attachment-download-via-get-files-key