{"api_version":"1","generated_at":"2026-08-25T04:49:29+00:00","cve":"CVE-2026-54741","urls":{"html":"https://cve.report/CVE-2026-54741","api":"https://cve.report/api/cve/CVE-2026-54741.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-54741","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-54741"},"summary":{"title":"Lemmy: Blocked users can edit private messages sent before the block","description":"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.","state":"PUBLISHED","assigner":"GitHub_M","published_at":"2026-08-19 21:16:58","updated_at":"2026-08-20 14:17:14"},"problem_types":["CWE-862","CWE-862 CWE-862: Missing 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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.","Type":"Description","Title":"Lemmy: Blocked users can edit private messages sent before the b"}]}}}