{"id":"CVE-2026-6608","state":"PUBLISHED","title":"lm-sys fastchat Arena Side-by-Side View add_text control flow","description":"A vulnerability was detected in lm-sys fastchat up to 0.2.36. Impacted is the function add_text of the component Arena Side-by-Side View Handler. The manipulation results in incorrect control flow. The attack can be launched remotely. The exploit is now public and may be used. The root cause was fixed in commit 34eca62 for gradio_block_arena_named.py, but three other files were missed.","publishedAt":"2026-04-20T05:15:12.337Z","updatedAt":"2026-04-20T14:57:55.071Z","severity":{"score":6.9,"label":"Medium","version":"4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P","source":"VulDB"},"assigner":"VulDB","products":["lm-sys fastchat"],"affected":[{"vendor":"lm-sys","product":"fastchat","versions":[{"version":"0.2.0","status":"affected"},{"version":"0.2.1","status":"affected"},{"version":"0.2.2","status":"affected"},{"version":"0.2.3","status":"affected"},{"version":"0.2.4","status":"affected"},{"version":"0.2.5","status":"affected"},{"version":"0.2.6","status":"affected"},{"version":"0.2.7","status":"affected"},{"version":"0.2.8","status":"affected"},{"version":"0.2.9","status":"affected"},{"version":"0.2.10","status":"affected"},{"version":"0.2.11","status":"affected"},{"version":"0.2.12","status":"affected"},{"version":"0.2.13","status":"affected"},{"version":"0.2.14","status":"affected"},{"version":"0.2.15","status":"affected"},{"version":"0.2.16","status":"affected"},{"version":"0.2.17","status":"affected"},{"version":"0.2.18","status":"affected"},{"version":"0.2.19","status":"affected"},{"version":"0.2.20","status":"affected"},{"version":"0.2.21","status":"affected"},{"version":"0.2.22","status":"affected"},{"version":"0.2.23","status":"affected"},{"version":"0.2.24","status":"affected"},{"version":"0.2.25","status":"affected"},{"version":"0.2.26","status":"affected"},{"version":"0.2.27","status":"affected"},{"version":"0.2.28","status":"affected"},{"version":"0.2.29","status":"affected"},{"version":"0.2.30","status":"affected"},{"version":"0.2.31","status":"affected"},{"version":"0.2.32","status":"affected"},{"version":"0.2.33","status":"affected"},{"version":"0.2.34","status":"affected"},{"version":"0.2.35","status":"affected"},{"version":"0.2.36","status":"affected"}],"cpes":["cpe:2.3:a:lm-sys:fastchat:*:*:*:*:*:*:*:*"],"modules":["Arena Side-by-Side View Handler"]}],"references":["https://vuldb.com/vuln/358243","https://vuldb.com/vuln/358243/cti","https://vuldb.com/submit/792228","https://github.com/lm-sys/FastChat/issues/3834","https://gist.github.com/YLChen-007/e45039d23e698222d887ee09735d9d36","https://github.com/lm-sys/FastChat/"],"weaknesses":["CWE-670"],"ingestedAt":"2026-10-29T20:12:49.727Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/6xxx/CVE-2026-6608.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-6608","state":"PUBLISHED","datePublished":"2026-04-20T05:15:12.337Z","dateUpdated":"2026-04-20T14:57:55.071Z","assignerShortName":"VulDB","assignerOrgId":"1af790b2-7ee1-4545-860a-a788eba489b5","dateReserved":"2026-04-19T15:59:43.122Z"},"containers":{"cna":{"title":"lm-sys fastchat Arena Side-by-Side View add_text control flow","descriptions":[{"lang":"en","value":"A vulnerability was detected in lm-sys fastchat up to 0.2.36. Impacted is the function add_text of the component Arena Side-by-Side View Handler. The manipulation results in incorrect control flow. The attack can be launched remotely. The exploit is now public and may be used. The root cause was fixed in commit 34eca62 for gradio_block_arena_named.py, but three other files were missed."}],"affected":[{"vendor":"lm-sys","product":"fastchat","versions":[{"version":"0.2.0","status":"affected"},{"version":"0.2.1","status":"affected"},{"version":"0.2.2","status":"affected"},{"version":"0.2.3","status":"affected"},{"version":"0.2.4","status":"affected"},{"version":"0.2.5","status":"affected"},{"version":"0.2.6","status":"affected"},{"version":"0.2.7","status":"affected"},{"version":"0.2.8","status":"affected"},{"version":"0.2.9","status":"affected"},{"version":"0.2.10","status":"affected"},{"version":"0.2.11","status":"affected"},{"version":"0.2.12","status":"affected"},{"version":"0.2.13","status":"affected"},{"version":"0.2.14","status":"affected"},{"version":"0.2.15","status":"affected"},{"version":"0.2.16","status":"affected"},{"version":"0.2.17","status":"affected"},{"version":"0.2.18","status":"affected"},{"version":"0.2.19","status":"affected"},{"version":"0.2.20","status":"affected"},{"version":"0.2.21","status":"affected"},{"version":"0.2.22","status":"affected"},{"version":"0.2.23","status":"affected"},{"version":"0.2.24","status":"affected"},{"version":"0.2.25","status":"affected"},{"version":"0.2.26","status":"affected"},{"version":"0.2.27","status":"affected"},{"version":"0.2.28","status":"affected"},{"version":"0.2.29","status":"affected"},{"version":"0.2.30","status":"affected"},{"version":"0.2.31","status":"affected"},{"version":"0.2.32","status":"affected"},{"version":"0.2.33","status":"affected"},{"version":"0.2.34","status":"affected"},{"version":"0.2.35","status":"affected"},{"version":"0.2.36","status":"affected"}],"cpes":["cpe:2.3:a:lm-sys:fastchat:*:*:*:*:*:*:*:*"],"modules":["Arena Side-by-Side View Handler"]}],"references":[{"url":"https://vuldb.com/vuln/358243","name":"VDB-358243 | lm-sys fastchat Arena Side-by-Side View add_text control flow","tags":["vdb-entry","technical-description"]},{"url":"https://vuldb.com/vuln/358243/cti","name":"VDB-358243 | CTI Indicators (IOB, IOC, IOA)","tags":["signature","permissions-required"]},{"url":"https://vuldb.com/submit/792228","name":"Submit #792228 | LM-Sys FastChat <= 0.2.36 Content Moderation Bypass (CWE-670)","tags":["third-party-advisory"]},{"url":"https://github.com/lm-sys/FastChat/issues/3834","tags":["issue-tracking"]},{"url":"https://gist.github.com/YLChen-007/e45039d23e698222d887ee09735d9d36","tags":["exploit"]},{"url":"https://github.com/lm-sys/FastChat/","tags":["product"]}],"metrics":[{"cvssV4_0":{"version":"4.0","baseScore":6.9,"vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P","baseSeverity":"MEDIUM"}},{"cvssV3_1":{"version":"3.1","baseScore":5.3,"vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N/E:P/RL:X/RC:R","baseSeverity":"MEDIUM"}},{"cvssV3_0":{"version":"3.0","baseScore":5.3,"vectorString":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N/E:P/RL:X/RC:R","baseSeverity":"MEDIUM"}},{"cvssV2_0":{"version":"2.0","baseScore":5,"vectorString":"AV:N/AC:L/Au:N/C:N/I:P/A:N/E:POC/RL:ND/RC:UR"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-670","type":"CWE","lang":"en","description":"Incorrect Control Flow"}]}],"providerMetadata":{"shortName":"VulDB","orgId":"1af790b2-7ee1-4545-860a-a788eba489b5","dateUpdated":"2026-04-20T05:15:12.337Z"},"timeline":[{"time":"2026-04-19T00:00:00.000Z","lang":"en","value":"Advisory disclosed"},{"time":"2026-04-19T02:00:00.000Z","lang":"en","value":"VulDB entry created"},{"time":"2026-04-19T18:04:52.000Z","lang":"en","value":"VulDB entry last update"}],"credits":[{"lang":"en","value":"Eric-f (VulDB User)","type":"reporter"}]},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-04-20T14:57:43.886595Z","id":"CVE-2026-6608","options":[{"Exploitation":"poc"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-04-20T14:57:55.071Z"}}]}}}