{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-44988","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","state":"PUBLISHED","assignerShortName":"GitHub_M","dateReserved":"2026-05-08T16:23:33.265Z","datePublished":"2026-05-27T14:26:50.063Z","dateUpdated":"2026-05-29T15:16:13.607Z"},"containers":{"cna":{"title":"LibVNCClient Tight Gradient decoding allows malicious server-triggered heap/stack OOB writes","problemTypes":[{"descriptions":[{"cweId":"CWE-787","lang":"en","description":"CWE-787: Out-of-bounds Write","type":"CWE"}]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":8.8,"baseSeverity":"HIGH","confidentialityImpact":"HIGH","integrityImpact":"HIGH","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"REQUIRED","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","version":"3.1"}}],"references":[{"name":"https://github.com/LibVNC/libvncserver/security/advisories/GHSA-jcc5-8wj4-7c58","tags":["x_refsource_CONFIRM"],"url":"https://github.com/LibVNC/libvncserver/security/advisories/GHSA-jcc5-8wj4-7c58"},{"name":"https://github.com/LibVNC/libvncserver/commit/5b270544b85233668b98161323297d418a8f5fd1","tags":["x_refsource_MISC"],"url":"https://github.com/LibVNC/libvncserver/commit/5b270544b85233668b98161323297d418a8f5fd1"}],"affected":[{"vendor":"LibVNC","product":"libvncserver","versions":[{"version":"<= 0.9.15","status":"affected"}]}],"providerMetadata":{"orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M","dateUpdated":"2026-05-27T14:26:50.063Z"},"descriptions":[{"lang":"en","value":"LibVNCClient is a library for easy implementation of a VNC client. In 0.9.15 and earlier, LibVNCClient's Tight encoding decoder uses fixed-size 2048-pixel scratch buffers for the Gradient filter, but it does not reject Tight rectangles whose width is larger than 2048 pixels. A malicious VNC server can send a crafted FramebufferUpdate rectangle using Tight encoding with NoZlib | ExplicitFilter and the Gradient filter. When a LibVNCClient-based client connects, the client processes the server-controlled rectangle width and writes beyond fixed-size Gradient buffers. This vulnerability is fixed with commit 5b270544b85233668b98161323297d418a8f5fd1."}],"source":{"advisory":"GHSA-jcc5-8wj4-7c58","discovery":"UNKNOWN"}},"adp":[{"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-05-29T03:55:55.774539Z","id":"CVE-2026-44988","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-05-29T15:16:13.607Z"}}]}}