{"id":"CVE-2026-103501","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-103501","generatedAt":"2026-10-28T03:58:07.470Z","title":"Heap buffer overflow in the HLL sketch deserialization of Apache DataSketches C++ (repo: datasketches-cpp).","description":"Heap buffer overflow in the HLL sketch deserialization of Apache DataSketches C++ (repo: datasketches-cpp).\n\nWhen deserializing a sketch in LIST mode, from either a byte buffer or a stream, the coupon count was read from the input and used as the number of entries to copy into a fixed buffer of 8 entries, without checking it against the buffer's capacity. A crafted sketch could cause a write of up to 988 bytes past the end of this internal heap buffer. This can corrupt heap memory, causing a crash and potentially enabling further exploitation.\n\nThis issue affects Apache DataSketches C++: from 1.0.0-incubating before 5.3.0. Only applications that deserialize HLL sketches from untrusted sources are affected.\n\nUsers are recommended to upgrade to version 5.3.0, which fixes this issue.","published":"2026-10-10T11:17:35.000Z","lastModified":"2026-10-16T16:16:53.000Z","status":"Undergoing Analysis","sourceIdentifier":"security@apache.org","cvss":{"version":"3.1","score":9.8,"severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"},"cwe":["CWE-122","CWE-1284"],"affected":[],"epss":{"score":0.00555,"percentile":0.46128,"date":"2026-10-27","history":[{"date":"2026-10-11","score":0.00214,"percentile":0.10794}]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.56%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[{"kind":"scored","label":"Newly scored","at":"2026-10-16T17:00:51.000Z","detail":{"from":null,"score":"9.8","severity":"CRITICAL","fromSeverity":null},"summary":"Now scored CVSS 9.8 CRITICAL."},{"kind":"new","label":"New CVE","at":"2026-10-10T11:17:35.000Z","detail":{"score":null,"severity":null,"publishedAt":"2026-10-10T11:17:34.853Z"},"summary":"New CVE, critical severity (CVSS 9.8)."}],"references":[{"url":"https://github.com/apache/datasketches-cpp/releases/tag/5.3.0","source":"security@apache.org"},{"url":"https://lists.apache.org/thread/n2oc2j841dzsv4239jjp08of66bo79c5","source":"security@apache.org"},{"url":"http://www.openwall.com/lists/oss-security/2026/10/10/2","source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-103501","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}