{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-54741", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-06-15T23:12:41.964Z", "datePublished": "2026-08-19T20:13:05.201Z", "dateUpdated": "2026-08-19T20:13:05.201Z"}, "containers": {"cna": {"title": "Lemmy: Blocked users can edit private messages sent before the block", "problemTypes": [{"descriptions": [{"cweId": "CWE-862", "lang": "en", "description": "CWE-862: Missing Authorization", "type": "CWE"}]}], "metrics": [{"cvssV4_0": {"attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "LOW", "userInteraction": "NONE", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "LOW", "vulnAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "baseScore": 5.3, "baseSeverity": "MEDIUM", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N", "version": "4.0"}}], "references": [{"name": "https://github.com/LemmyNet/lemmy/security/advisories/GHSA-46g9-847m-qf8r", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/LemmyNet/lemmy/security/advisories/GHSA-46g9-847m-qf8r"}, {"name": "https://github.com/LemmyNet/lemmy/pull/6472", "tags": ["x_refsource_MISC"], "url": "https://github.com/LemmyNet/lemmy/pull/6472"}, {"name": "https://github.com/LemmyNet/lemmy/pull/6476", "tags": ["x_refsource_MISC"], "url": "https://github.com/LemmyNet/lemmy/pull/6476"}, {"name": "https://github.com/LemmyNet/lemmy/commit/051b317c9d14b91972bb372c67f319d6900beb93", "tags": ["x_refsource_MISC"], "url": "https://github.com/LemmyNet/lemmy/commit/051b317c9d14b91972bb372c67f319d6900beb93"}, {"name": "https://github.com/LemmyNet/lemmy/commit/2d169d630b86b9351e4b1dca451214b741f46150", "tags": ["x_refsource_MISC"], "url": "https://github.com/LemmyNet/lemmy/commit/2d169d630b86b9351e4b1dca451214b741f46150"}, {"name": "https://github.com/LemmyNet/lemmy/releases/tag/0.19.19", "tags": ["x_refsource_MISC"], "url": "https://github.com/LemmyNet/lemmy/releases/tag/0.19.19"}, {"name": "https://github.com/LemmyNet/lemmy/releases/tag/1.0.0-alpha.18", "tags": ["x_refsource_MISC"], "url": "https://github.com/LemmyNet/lemmy/releases/tag/1.0.0-alpha.18"}], "affected": [{"vendor": "LemmyNet", "product": "lemmy", "versions": [{"version": "< 0.19.19", "status": "affected"}, {"version": ">= 1.0.0-alpha.0, < 1.0.0-alpha.18", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-08-19T20:13:05.201Z"}, "descriptions": [{"lang": "en", "value": "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."}], "source": {"advisory": "GHSA-46g9-847m-qf8r", "discovery": "UNKNOWN"}}}}

{}

{}

{}

{}