{"id":"CVE-2026-104608","kind":"vulnerability","aliases":["CVE-2026-104608"],"related":[],"title":"GitHub Enterprise Server: SSH-authenticated users can run commands via Git service","description":"A remote code execution vulnerability was identified in GitHub Enterprise Server in the Git service (babeld). babeld held references into internal collections while calling into the SSH library, where a re-entrant callback could modify a collection and invalidate those references. An attacker with an account and SSH access to the instance could leverage this use-after-free into a controlled write and run arbitrary commands as babeld, including disclosure of its environment secrets. Exploitation required per-build memory offsets; failed attempts crashed babeld. This affected all releases prior to 3.23 and was fixed in 3.22.3, 3.21.8, 3.20.10, and 3.19.14. This vulnerability was reported via the GitHub Bug Bounty program.","summary":"A use-after-free in the babeld Git service of GitHub Enterprise Server lets an attacker with an account and SSH access turn a memory bug into arbitrary command execution. The attacker runs commands as babeld and can read its environment secrets.","severity":"high","cvss":7.7,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["git","github-enterprise-server","self-hosted","ssh","vendor"],"not_affected_if":["managed-hosting","no-untrusted-accounts","ssh-disabled"],"how_to_check":"- Check the installed GitHub Enterprise Server version in the site admin dashboard and compare it with the fixed versions below.\n- Confirm whether SSH access is enabled for the instance and which users can authenticate over it.","fix":"- Upgrade to `3.22.3` on the 3.22 line\n- Upgrade to `3.21.8` on the 3.21 line\n- Upgrade to `3.20.10` on the 3.20 line\n- Upgrade to `3.19.14` on the 3.19 line","status":"open","published_at":"2026-11-03T23:17:24+00:00","first_seen_at":"2026-11-03T23:45:12+00:00","triaged_at":"2026-11-03T23:45:29+00:00","updated_at":"2026-11-03T23:45:29+00:00","category":"vendor","confidence":0.7,"triage":{"at":"2026-11-03T23:45:29Z","model":"claude-haiku-5-5","output":{"fix":"- Upgrade to `3.22.3` on the 3.22 line\n- Upgrade to `3.21.8` on the 3.21 line\n- Upgrade to `3.20.10` on the 3.20 line\n- Upgrade to `3.19.14` on the 3.19 line","reach":"network","title":"GitHub Enterprise Server: SSH-authenticated users can run commands via Git service","impact":"high","summary":"A use-after-free in the babeld Git service of GitHub Enterprise Server lets an attacker with an account and SSH access turn a memory bug into arbitrary command execution. The attacker runs commands as babeld and can read its environment secrets.","audience":"businesses","category":"vendor","nicknames":[],"who_cares":["github-enterprise-server","self-hosted","git","ssh"],"confidence":0.7,"fix_status":"available","needs_auth":"yes","worst_case":"Attacker runs arbitrary commands as babeld and reads its environment secrets","analyst_note":"","how_to_check":"- Check the installed GitHub Enterprise Server version in the site admin dashboard and compare it with the fixed versions below.\n- Confirm whether SSH access is enabled for the instance and which users can authenticate over it.","plain_action":"","needs_analyst":false,"not_affected_if":["managed-hosting","ssh-disabled","no-untrusted-accounts"],"who_is_affected":"Self-hosted GitHub Enterprise Server instances on releases prior to 3.23 are affected. The attacker needs an account on the instance and SSH access, so instances where SSH is disabled or limited to trusted users have less exposure. GitHub.com and other managed deployments are not described as affected by the sources.","user_interaction":"no","needs_special_setup":"unknown","severity_if_unknown":"high"},"cost_usd":0.000741,"input_tokens":4261,"output_tokens":629,"severity_before":"high"},"analyst_status":null,"analyst_note":null,"search":"'-104608':16A,19A '-2026':15A,18A '3.19.14':175C '3.20.10':173C '3.21.8':172C '3.22.3':171C '3.23':166C 'access':52B,122C 'account':49B,119C 'affect':161C 'arbitrari':58B,139C 'attack':46B,62B,116C 'attempt':157C 'authent':6A 'babeld':37B,66B,88C,89C,142C,159C 'bounti':184C 'bug':56B,183C 'build':153C 'call':96C 'callback':106C 'code':75C 'collect':94C,110C 'command':10A,59B,64B,140C 'control':135C 'could':107C,126C 'crash':158C 'cve':14A,17A 'disclosur':144C 'enterpris':2A,23B,42B,82C 'entrant':105C 'environ':71B,147C 'execut':60B,76C 'exploit':149C 'fail':156C 'fix':169C 'free':34B,132C 'git':12A,20B,38B,86C 'github':1A,22B,41B,81C,182C 'github-enterprise-serv':21B 'held':90C 'host':27B 'identifi':79C 'includ':143C 'instanc':125C 'intern':93C 'invalid':112C 'let':44B 'leverag':127C 'librari':100C 'memori':55B,154C 'modifi':108C 'offset':155C 'per':152C 'per-build':151C 'prior':164C 'program':185C 're':104C 're-entr':103C 'read':69B 'refer':91C,114C 'releas':163C 'remot':74C 'report':179C 'requir':150C 'run':9A,63B,138C 'secret':72B,148C 'self':26B 'self-host':25B 'server':3A,24B,43B,83C 'servic':13A,39B,87C 'ssh':5A,28B,51B,99C,121C 'ssh-authent':4A 'turn':53B 'use':32B,130C 'use-after-fre':31B,129C 'user':7A 'vendor':29B 'via':11A,180C 'vulner':77C,177C 'write':136C","nicknames":[],"mitigations":[],"who_affected":"Self-hosted GitHub Enterprise Server instances on releases prior to 3.23 are affected. The attacker needs an account on the instance and SSH access, so instances where SSH is disabled or limited to trusted users have less exposure. GitHub.com and other managed deployments are not described as affected by the sources.","tier":"B","verified":{},"analyst_revisit_at":null,"fix_status":"available","audience":"businesses","plain_action":null,"pkeys":[],"ptokens":[],"labels":["git","githubenterpriseserver","high","selfhosted","ssh","vendor"],"campaign_type":null,"first_public_at":"2026-11-03T23:17:24+00:00","kev":null,"cvss_vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:L/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","cvss_by":"product-cna@github.com","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-104608","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-104608","severity":null,"published_at":"2026-11-03T23:17:24+00:00","modified_at":"2026-11-03T23:17:24+00:00","first_seen_at":"2026-11-03T23:45:12+00:00","fetched_at":"2026-11-03T23:45:12+00:00","note":null}],"documents":[],"notice":"Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai"}