Summary A vulnerability has been discovered in Agnai that permits attackers to upload image files at attacker-chosen location on the server. This issue can lead to image file uploads to unauthorized or unintended directories, including overwriting of existing images which may be used for defacement. This does not affect: agnai.chat installations using S3-compatible storage self-hosting that is not publicly exposed CWE-35: Path Traversal https://cwe.mitre.org/data/definitions/35.html CVSS4.0 – 2.3 Low CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N Details This is a path traversal vulnerability. An attacker can exploit this vulnerability by sending a specially crafted request to the editCharacter handler https://github.com/agnaistic/agnai/blob/75abbd5b0f5e48ddecc805365cf1574d05ee1ce5/srv/api/character.ts#L140: tsx POST /api/character/28cbe508-2fa9-4890-886e-61d73e22006c%2f%2e%2e%2f%2e%2e%2f%2e%2e%2f%2e%2e%2f%2e%2e%2f%61%70%70%2f%64%69%73%74%2f%64%61%6e%79%61%6e%67 HTTP/1.1 The path traversal character sequence makes it’s way into the id variable which is then string interpolated into filename. jsx export async function entityUpload(kind: string, id: string, attachment?: Attachment) { if (!attachment) return const filename = `${kind}-${id}` return upload(attachment, filename) } https://github.com/agnaistic/agnai/blob/75abbd5b0f5e48ddecc805365cf1574d05ee1ce5/srv/api/upload.ts#L55 No path normalization is conducted nor checked, so attackers can freely…Read More