CVE-2026-44637

{"id": "CVE-2026-44637", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Secondary", "source": "security-advisories@github.com", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 7.1, "attackVector": "LOCAL", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "REQUIRED", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "NONE"}, "impactScore": 5.2, "exploitabilityScore": 1.8}]}, "published": "2026-05-14T20:17:08.847", "references": [{"url": "https://github.com/saitoha/libsixel/security/advisories/GHSA-9jm7-77gr-qghv", "tags": ["Exploit", "Vendor Advisory"], "source": "security-advisories@github.com"}, {"url": "https://github.com/saitoha/libsixel/security/advisories/GHSA-9jm7-77gr-qghv", "tags": ["Exploit", "Vendor Advisory"], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Secondary", "source": "security-advisories@github.com", "description": [{"lang": "en", "value": "CWE-190"}, {"lang": "en", "value": "CWE-787"}]}, {"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "CWE-787"}]}], "descriptions": [{"lang": "en", "value": "libsixel is a SIXEL encoder/decoder implementation derived from kmiya's sixel. From to 1.8.7-r1, a signed integer overflow in the SIXEL parser's image-buffer doubling loop can lead to an out-of-bounds heap write in sixel_decode_raw_impl. context->pos_x grows by repeat_count on every sixel character with no upper bound check. Once pos_x approaches INT_MAX, the expression \"pos_x + repeat_count\" used to size the image buffer overflows signed int. Depending on how the overflow wraps, the resize check that should reject oversized buffers can be bypassed, after which a subsequent write computes a large attacker-influenced offset into image->data and writes past the allocation. Reachable from any caller that decodes attacker-supplied SIXEL data, including img2sixel. This vulnerability is fixed in 1.8.7-r2."}], "lastModified": "2026-05-15T17:55:03.837", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:saitoha:libsixel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "7E82CD3A-0E58-4567-81F9-C7010DFE4D1E", "versionEndExcluding": "1.8.7-r2", "versionStartIncluding": "0.11.0"}], "operator": "OR"}]}], "sourceIdentifier": "security-advisories@github.com"}