{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2026-77912 in the wild and no public exploit code.","fix":"No fix has been published for CVE-2026-77912 yet. Limit exposure of the affected software until one is available.","what":"CVE-2026-77912 is a high-severity cross-site scripting vulnerability in Github Enterprise Server, published on 22 Sep 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link."},"fix_prompt":"Check this codebase for CVE-2026-77912 and fix it if it is affected.\n\nWhat it is: CVE-2026-77912 is a high-severity cross-site scripting vulnerability in Github Enterprise Server, published on 22 Sep 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.\nExploitation: There is no known exploitation of CVE-2026-77912 in the wild and no public exploit code.\n\nAffected product: Github Enterprise Server. No package-level version data is available, so check the vendor advisory linked from the reference page.\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2026-77912/ (Markdown: https://insights.sbomify.com/CVE-2026-77912/index.md)","id":"CVE-2026-77912","markdown":"https://insights.sbomify.com/CVE-2026-77912/index.md","name":"CVE-2026-77912","record":{"aliases":["GHSA-6293-4rx2-2p57"],"analysis":{"component_type":"web_application","fix_type":"upgrade","impacts":["data_read","account_takeover"],"network_reachable":"yes","non_default_config":false,"product_category":"GitHub Enterprise Server","requires_auth":"low_privilege","summary":"Authenticated attackers can inject HTML attributes via Markdown to bypass CSP, read victim data, and perform actions as the victim.","user_interaction":"required","vuln_class":"xss"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_P","cpe":[{"product":"enterprise_server","vendor":"github"}],"cvss":{"score":7.4,"severity":"high","source":"cna","vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:P/VC:H/VI:H/VA:N/SC:L/SI:L/SA:N/AU:Y","version":"4.0"},"cwes":[{"id":"CWE-79","name":"Improper Neutralization of Input During Web Page Generation"}],"description":"A stored cross-site scripting (XSS) vulnerability was identified in GitHub Enterprise Server that allowed an authenticated attacker to inject arbitrary HTML attributes into rendered Markdown because the Markdown rendering pipeline rewrote quote characters in already-sanitized HTML without re-sanitizing the result. Crafted Markdown could abuse same-origin JavaScript gadgets to bypass Content Security Policy and gain control of the page DOM when viewed by another user. Successful exploitation could allow an attacker to read content visible to the victim, extract embedded CSRF tokens, perform state-changing actions as the victim, and exfiltrate data through same-origin writes. The payload could also propagate to repositories and organizations where the victim had write access. This vulnerability affected supported GitHub Enterprise Server releases in the 3.17, 3.18, 3.19, 3.20, 3.21, and 3.22 series and was fixed in versions 3.22.1, 3.21.6, 3.20.8, 3.19.12, 3.18.15, and 3.17.21. This vulnerability was reported via the GitHub Bug Bounty program.","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":null,"headline":"Cross-site scripting in Enterprise Server","id":"CVE-2026-77912","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"github:enterprise_server","products":["github:enterprise_server"],"type":"xss","year":"2026"},"n_packages":0,"n_references":6,"next":{"headline":"rConfig Core 8.0.0 \u003c 8.2.13 Core Path Traversal via Export Download Endpoint","id":"CVE-2026-77914"},"packages":[],"prev":{"headline":"Microsoft Office Word Information Disclosure Vulnerability","id":"CVE-2026-77911"},"products":["Enterprise Server"],"published":"2026-09-22","related":[{"cvss_score":10,"headline":"Auth bypass in Enterprise Server","id":"CVE-2024-4985","kev_date_added":null,"published":"2024-05-20"},{"cvss_score":9.8,"headline":"Missing authorization in GitHub Enterprise Server","id":"CVE-2022-23739","kev_date_added":null,"published":"2023-01-17"},{"cvss_score":9.8,"headline":"Improper Limitation of a Pathname to a Restricted Directory in GitHub Enterprise Server leading to RCE","id":"CVE-2022-46255","kev_date_added":null,"published":"2022-12-14"},{"cvss_score":9.8,"headline":"Improper access control in GitHub Enterprise Server allows self-hosted runners to execute outside their control group","id":"CVE-2021-22869","kev_date_added":null,"published":"2021-09-24"},{"cvss_score":9.5,"headline":"Auth bypass in Enterprise Server","id":"CVE-2024-9487","kev_date_added":null,"published":"2024-10-10"},{"cvss_score":9.5,"headline":"Auth bypass in GitHub Enterprise Server","id":"CVE-2024-6800","kev_date_added":null,"published":"2024-08-20"},{"cvss_score":9.3,"headline":"GitHub Enterprise Server notebook viewer vulnerable to Server-side request forgery","id":"CVE-2026-77987","kev_date_added":null,"published":"2026-09-22"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"US public information, NVD API terms","name":"NVD"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"no","exploitation":"none","technical_impact":"total"},"state":"PUBLISHED","updated":"2026-09-23","vendors":["GitHub"]},"summary":"Authenticated attackers can inject HTML attributes via Markdown to bypass CSP, read victim data, and perform actions as the victim.","url":"https://insights.sbomify.com/CVE-2026-77912/"}