CVE-2026-54741

Lemmy is a link aggregator and forum for the fediverse. Prior to 0.19.19 and 1.0.0-alpha.18, Lemmy blocks new private messages from a sender after the recipient blocks that sender, but the edit path skips the same block check. create_private_message checks the recipient's block list with PersonActions::read_block before inserting a message, while edit_private_message in crates/api/api_crud/src/private_message/update.rs only checks that the caller is orig_private_message.creator_id. The update then writes new content and returns the modified PrivateMessageView without consulting the recipient's block list, allowing a blocked sender to keep changing an old message that the recipient can still see and providing a post-block harassment path. This issue is fixed in versions 0.19.19 and 1.0.0-alpha.18.

CVSS

No CVSS.

References

Link	Resource
https://github.com/LemmyNet/lemmy/commit/051b317c9d14b91972bb372c67f319d6900beb93
https://github.com/LemmyNet/lemmy/commit/2d169d630b86b9351e4b1dca451214b741f46150
https://github.com/LemmyNet/lemmy/pull/6472
https://github.com/LemmyNet/lemmy/pull/6476
https://github.com/LemmyNet/lemmy/releases/tag/0.19.19
https://github.com/LemmyNet/lemmy/releases/tag/1.0.0-alpha.18
https://github.com/LemmyNet/lemmy/security/advisories/GHSA-46g9-847m-qf8r
https://github.com/LemmyNet/lemmy/security/advisories/GHSA-46g9-847m-qf8r

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-19 21:16

Updated : 2026-09-09 21:15

NVD link : CVE-2026-54741

Mitre link : CVE-2026-54741

CVE.ORG link : CVE-2026-54741

JSON object : View

Products Affected

No product.

CWE

CWE-862

Missing Authorization

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