{"affected":[{"product":"UltraVNC","source":"CNA: certcc","vendor":"UltraVNC","versions":[{"lessThanOrEqual":"1.8.2.6","status":"affected","version":"1.8.2.4","versionType":"custom"}]},{"product":"TightVNC","source":"CNA: certcc","vendor":"Glavsoft (TightVNC)","versions":[{"lessThanOrEqual":"1.3.10","status":"affected","version":"1.3.10","versionType":"custom"}]}],"cveId":"CVE-2026-128321","cwes":["CWE-122"],"description":"Tight JPEG decoding in TightVNC and UltraVNC viewers contains a heap-based buffer overflow because an attacker-controlled framebuffer rectangle width is not validated against a fixed-size decoding buffer. A malicious VNC server can cause an out-of-bounds heap write when a user connects, resulting in application crash and potentially other memory-corruption impacts.","epss":null,"exploits":[],"kev":null,"metrics":[],"modifiedAt":1794535551969,"publishedAt":1794528512021,"references":[{"source":"CNA: certcc","tags":[],"url":"https://www.tightvnc.com/"},{"source":"CNA: certcc","tags":[],"url":"https://github.com/ultravnc/ultravnc"},{"source":"ADP: CVE","tags":[],"url":"https://www.kb.cert.org/vuls/id/644655"}],"remediation":[],"revision":"2ee830f84eaa98f2a397fb55549da073e7abe4fee2c13581765006291e317ce9","sources":[{"modifiedAt":1794535551969,"name":"CNA: certcc","retrievedAt":1794539342142,"url":"https://www.cve.org/CVERecord?id=CVE-2026-128321"}],"ssvc":null,"status":"published","title":"Tight JPEG decoding in TightVNC and UltraVNC viewers contains a heap-based buffer overflow vulnerability","updatedAt":1794539342142}