{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-33018","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","state":"PUBLISHED","assignerShortName":"GitHub_M","dateReserved":"2026-03-17T17:22:14.666Z","datePublished":"2026-04-14T21:45:42.261Z","dateUpdated":"2026-04-16T13:53:25.060Z"},"containers":{"cna":{"title":"libsixel: Use-After-Free in load_gif()","problemTypes":[{"descriptions":[{"cweId":"CWE-416","lang":"en","description":"CWE-416: Use After Free","type":"CWE"}]}],"metrics":[{"cvssV3_1":{"attackComplexity":"HIGH","attackVector":"LOCAL","availabilityImpact":"HIGH","baseScore":7,"baseSeverity":"HIGH","confidentialityImpact":"HIGH","integrityImpact":"HIGH","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"REQUIRED","vectorString":"CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H","version":"3.1"}}],"references":[{"name":"https://github.com/saitoha/libsixel/security/advisories/GHSA-w46f-jr9f-rgvp","tags":["x_refsource_CONFIRM"],"url":"https://github.com/saitoha/libsixel/security/advisories/GHSA-w46f-jr9f-rgvp"},{"name":"https://github.com/saitoha/libsixel/releases/tag/v1.8.7-r1","tags":["x_refsource_MISC"],"url":"https://github.com/saitoha/libsixel/releases/tag/v1.8.7-r1"}],"affected":[{"vendor":"saitoha","product":"libsixel","versions":[{"version":"< 1.8.7-rc1","status":"affected"}]}],"providerMetadata":{"orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M","dateUpdated":"2026-04-14T21:45:42.261Z"},"descriptions":[{"lang":"en","value":"libsixel is a SIXEL encoder/decoder implementation derived from kmiya's sixel. Versions 1.8.7 and prior contain a Use-After-Free vulnerability via the load_gif() function in fromgif.c, where a single sixel_frame_t object is reused across all frames of an animated GIF and gif_init_frame() unconditionally frees and reallocates frame->pixels between frames without consulting the object's reference count. Because the public API explicitly provides sixel_frame_ref() to retain a frame and sixel_frame_get_pixels() to access the raw pixel buffer, a callback following this documented usage pattern will hold a dangling pointer after the second frame is decoded, resulting in a heap use-after-free confirmed by ASAN. Any application using sixel_helper_load_image_file() with a multi-frame callback to process user-supplied animated GIFs is affected, with a reliable crash as the minimum impact and potential for code execution. This issue has been fixed in version 1.8.7-r1."}],"source":{"advisory":"GHSA-w46f-jr9f-rgvp","discovery":"UNKNOWN"}},"adp":[{"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-04-16T13:52:34.921283Z","id":"CVE-2026-33018","options":[{"Exploitation":"poc"},{"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":"2026-04-16T13:53:25.060Z"}}]}}