{"id":"CVE-2026-1355","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-1355","generatedAt":"2026-10-28T02:11:11.572Z","title":"A Missing Authorization vulnerability was identified in GitHub Enterprise Server that allowed an attacker to upload unauthorized content to another user’s repository migration export due to a missing authorization check in the repository migration…","description":"A Missing Authorization vulnerability was identified in GitHub Enterprise Server that allowed an attacker to upload unauthorized content to another user’s repository migration export due to a missing authorization check in the repository migration upload endpoint. By supplying the migration identifier, an attacker could overwrite or replace a victim’s migration archive, potentially causing victims to download attacker-controlled repository data during migration restores or automated imports. An attacker would require authentication to the victim's GitHub Enterprise Server instance. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.20 and was fixed in versions 3.19.2, 3.18.5, 3.17.11, 3.16.14, 3.15.18, 3.14.23. This vulnerability was reported via the GitHub Bug Bounty program.","published":"2026-02-18T21:16:23.000Z","lastModified":"2026-06-17T10:15:39.000Z","status":"Analyzed","sourceIdentifier":"product-cna@github.com","cvss":{"version":"4.0","score":6,"severity":"MEDIUM","vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M"},"cwe":["CWE-862"],"affected":["github/enterprise server"],"epss":{"score":0.00457,"percentile":0.39373,"date":"2026-10-26","history":[]},"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 (0.46%). Track it; it rarely justifies an emergency change on its own."},"changes":[],"references":[{"url":"https://docs.github.com/en/enterprise-server@3.14/admin/release-notes#3.14.23","tags":["Product","Release Notes"],"source":"product-cna@github.com"},{"url":"https://docs.github.com/en/enterprise-server@3.15/admin/release-notes#3.15.18","tags":["Product","Release Notes"],"source":"product-cna@github.com"},{"url":"https://docs.github.com/en/enterprise-server@3.16/admin/release-notes#3.16.14","tags":["Product","Release Notes"],"source":"product-cna@github.com"},{"url":"https://docs.github.com/en/enterprise-server@3.17/admin/release-notes#3.17.11","tags":["Product","Release Notes"],"source":"product-cna@github.com"},{"url":"https://docs.github.com/en/enterprise-server@3.18/admin/release-notes#3.18.5","tags":["Product","Release Notes"],"source":"product-cna@github.com"},{"url":"https://docs.github.com/en/enterprise-server@3.19/admin/release-notes#3.19.2","tags":["Product","Release Notes"],"source":"product-cna@github.com"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-1355","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."}