{"id":"CVE-2026-111458","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-111458","generatedAt":"2026-10-28T09:27:35.481Z","title":"This miscalculation results in a 3-byte heap-based buffer overflow on every invocation of the function with valid inputs.","description":"The fanx_fingerprint function in ssl/sslxprint.c of ssldump allocates a heap buffer for formatting FAN/1 X.509 certificate fingerprints. The allocation size is computed as strlen(b64) + strlen(hex) + 31, but the format string \"fan1:x509:server:passive:%s:sha256:%s\" contains 33 fixed characters in addition to the two variable-length fields and a null terminator, requiring strlen(b64) + strlen(hex) + 34 bytes. This miscalculation results in a 3-byte heap-based buffer overflow on every invocation of the function with valid inputs. The overflow occurs because sprintf writes the full formatted string into the undersized heap buffer without bounds checking. An attacker who can supply a crafted pcap file containing a TLS X.509 certificate to a user running ssldump with FAN/1 fingerprinting enabled (for example with the -j -N options) can trigger the overflow. The resulting heap corruption may lead to denial of service through a crash or, in a worst-case scenario, arbitrary code execution in the context of the user running ssldump. The vulnerability is deterministic and requires no special privileges beyond the ability to provide input to the tool.","published":"2026-10-16T06:17:10.000Z","lastModified":"2026-10-16T20:04:30.000Z","status":"Deferred","sourceIdentifier":"5a6e4751-2f3f-4070-9419-94fb35b644e8","cvss":{"version":"4.0","score":6.8,"severity":"MEDIUM","vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M"},"cwe":["CWE-122","CWE-787"],"affected":[],"epss":{"score":0.00094,"percentile":0.00578,"date":"2026-10-27","history":[{"date":"2026-10-16","score":0.00094,"percentile":0.00567}]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.09%). Track it; it rarely justifies an emergency change on its own."},"changes":[{"kind":"new","label":"New CVE","at":"2026-10-16T06:17:10.000Z","detail":{"score":"6.8","severity":"MEDIUM","publishedAt":"2026-10-16T06:17:09.510Z"},"summary":"New CVE, medium severity (CVSS 6.8)."}],"references":[{"url":"https://github.com/adulau/ssldump/commit/8ad55683cc0186600c085d33be5a5b627db78467","source":"5a6e4751-2f3f-4070-9419-94fb35b644e8"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-111458","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."}