CVE-2026-109206

Description

LogicalDOC Community Edition through 9.3 contains a username enumeration vulnerability that allows unauthenticated attackers to identify valid accounts because the AvatarServlet (/avatar) performs no session validation. Attackers can supply usernames or numeric IDs in the userId parameter and compare 1x1 transparent images against real avatars to enumerate users and retrieve profile pictures.

References

• https://github.com/logicaldoc/community
• https://github.com/logicaldoc/community/blob/9.3/logicaldoc-webapp/src/main/java/com/logicaldoc/web/AvatarServlet.java#L63
• https://github.com/logicaldoc/community/commit/4e93a69526ae7fe50f670b85b3fc57181f3de3f7
• https://github.com/logicaldoc/community/discussions/119
• https://www.vulncheck.com/advisories/logicaldoc-community-edition-through-9.3-username-enumeration-via-avatarservlet