{"id":"CVE-2026-3854","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-3854","generatedAt":"2026-10-31T06:00:39.610Z","title":"An improper neutralization of special elements vulnerability was identified in GitHub Enterprise Server that allowed an attacker with push access to a repository to achieve remote code execution on the instance.","description":"An improper neutralization of special elements vulnerability was identified in GitHub Enterprise Server that allowed an attacker with push access to a repository to achieve remote code execution on the instance. During a git push operation, user-supplied push option values were not properly sanitized before being included in internal service headers. Because the internal header format used a delimiter character that could also appear in user input, an attacker could inject additional metadata fields through crafted push option values. This vulnerability was reported via the GitHub Bug Bounty program and has been fixed in GitHub Enterprise Server versions 3.14.25, 3.15.20, 3.16.16, 3.17.13, 3.18.7 and 3.19.4.","published":"2026-03-10T18:19:06.000Z","lastModified":"2026-06-17T10:44:21.000Z","status":"Modified","sourceIdentifier":"product-cna@github.com","cvss":{"version":"4.0","score":8.7,"severity":"HIGH","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/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-77"],"affected":["github/enterprise server"],"epss":{"score":0.39796,"percentile":0.98621,"date":"2026-10-30","history":[{"date":"2026-09-24","score":0.01448,"percentile":0.72183},{"date":"2026-10-25","score":0.39109,"percentile":0.98585}]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"urgent","text":"EPSS puts the probability of exploitation in the next 30 days at 39.8%, higher than 99% of all known CVEs. Patch or mitigate before the next change window."},"changes":[{"kind":"epss","label":"EPSS jump","at":"2026-10-25T00:00:00.000Z","detail":{"to":0.39109,"from":0.01504,"percentile":0.98585},"summary":"EPSS moved from 1.5% to 39.1% probability of exploitation in the next thirty days."},{"kind":"epss","label":"EPSS jump","at":"2026-09-24T00:00:00.000Z","detail":{"to":0.01448,"from":0.40027,"percentile":0.72183},"summary":"EPSS moved from 40.0% to 1.4% probability of exploitation in the next thirty days."}],"references":[{"url":"https://docs.github.com/en/enterprise-server@3.14/admin/release-notes#3.14.25","source":"product-cna@github.com"},{"url":"https://docs.github.com/en/enterprise-server@3.15/admin/release-notes#3.15.20","source":"product-cna@github.com"},{"url":"https://docs.github.com/en/enterprise-server@3.16/admin/release-notes#3.16.16","source":"product-cna@github.com"},{"url":"https://docs.github.com/en/enterprise-server@3.17/admin/release-notes#3.17.13","source":"product-cna@github.com"},{"url":"https://docs.github.com/en/enterprise-server@3.18/admin/release-notes#3.18.7","source":"product-cna@github.com"},{"url":"https://docs.github.com/en/enterprise-server@3.19/admin/release-notes#3.19.4","source":"product-cna@github.com"},{"url":"https://www.wiz.io/blog/github-rce-vulnerability-cve-2026-3854","source":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-3854","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."}