{"apiVersion":"1.0","identifier":"CVE-2026-54741","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.","publishedAt":"2026-08-19T21:16:58","lastModifiedAt":"2026-08-20T14:17:14","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-54741","cvssScore":5.3,"cvssVector":"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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","epssProbability":0.00354,"riskScore":0.55,"affectedProduct":"Lemmy","affectedVersions":"<0.19.19, <1.0.0-alpha.18","vulnerabilityType":"Web app","operatingSystems":[],"links":{"self":"https://www.redsauce.net/api/cves/CVE-2026-54741","webPages":{"es":"https://www.redsauce.net/es/cves/CVE-2026-54741","en":"https://www.redsauce.net/en/cves/CVE-2026-54741","fr":"https://www.redsauce.net/fr/cves/CVE-2026-54741","pt":"https://www.redsauce.net/pt/cves/CVE-2026-54741","de":"https://www.redsauce.net/de/cves/CVE-2026-54741","sk":"https://www.redsauce.net/sk/cves/CVE-2026-54741","el":"https://www.redsauce.net/el/cves/CVE-2026-54741"},"source":"https://nvd.nist.gov/vuln/detail/CVE-2026-54741"}}