{"id":"CVE-2014-7169","kind":"vulnerability","aliases":["CVE-2014-7169"],"related":[],"title":"GNU Bourne-Again Shell (Bash): GNU Bourne-Again Shell (Bash) Arbitrary Code Execution Vulnerability","description":"GNU Bash through 4.3 bash43-025 processes trailing strings after certain malformed function definitions in the values of environment variables, which allows remote attackers to write to files or possibly have unknown other impact via a crafted environment, as demonstrated by vectors involving the ForceCommand feature in OpenSSH sshd, the mod_cgi and mod_cgid modules in the Apache HTTP Server, scripts executed by unspecified DHCP clients, and other situations in which setting the environment occurs across a privilege boundary from Bash execution.  NOTE: this vulnerability exists because of an incomplete fix for CVE-2014-6271.","summary":"GNU Bash through 4.3 executes trailing commands hidden after function definitions in environment variable values, so a remote attacker who can set an environment variable reaches code execution. This is the incomplete fix to Shellshock (CVE-2014-6271) and is listed as actively exploited.","severity":"critical","cvss":10.0,"epss":0.9994,"exploited":true,"exploited_at":"2022-01-28T00:00:00+00:00","products":[{"name":"GNU Bourne-Again Shell (Bash)","fixed":[],"affected":"","ecosystem":"vendor"}],"ecosystems":["vendor"],"tags":["bash","cgi","dhcp","exploited","linux","runtime","self-hosted"],"not_affected_if":["managed-hosting","no-bash-in-path","patched-bash"],"how_to_check":"Run: bash --version and compare against the patched release from your OS vendor.\nTest: env 'x=() { :;}; echo VULNERABLE' bash -c 'echo test' (prints VULNERABLE when unpatched).\nCheck whether CGI scripts or DHCP clients pass HTTP headers into environment variables.","fix":"Update bash to the patched package from your OS vendor (Bash 4.3 patch 25 or later is the upstream fix level) and restart services that spawn bash.\nRe-run the env test above after patching to confirm.","status":"open","published_at":"2014-09-25T01:55:04+00:00","first_seen_at":"2026-10-23T19:11:53+00:00","triaged_at":"2026-10-23T21:28:59+00:00","updated_at":"2026-10-23T21:57:35+00:00","category":"runtime","confidence":0.9,"triage":{"at":"2026-10-23T21:28:59Z","model":"claude-haiku-5-5","output":{"fix":"Update bash to the patched package from your OS vendor (Bash 4.3 patch 25 or later is the upstream fix level) and restart services that spawn bash.\nRe-run the env test above after patching to confirm.","reach":"network","impact":"high","summary":"GNU Bash through 4.3 executes trailing commands hidden after function definitions in environment variable values, so a remote attacker who can set an environment variable reaches code execution. This is the incomplete fix to Shellshock (CVE-2014-6271) and is listed as actively exploited.","category":"runtime","who_cares":["bash","self-hosted","linux","cgi","dhcp"],"confidence":0.9,"needs_auth":"no","worst_case":"Remote attacker runs arbitrary commands as the shell's user.","analyst_note":"Confirm the exact patched package versions per distro from the vendor advisories linked in the KEV entry; sources here do not list them.","how_to_check":"Run: bash --version and compare against the patched release from your OS vendor.\nTest: env 'x=() { :;}; echo VULNERABLE' bash -c 'echo test' (prints VULNERABLE when unpatched).\nCheck whether CGI scripts or DHCP clients pass HTTP headers into environment variables.","needs_analyst":true,"not_affected_if":["managed-hosting","no-bash-in-path","patched-bash"],"user_interaction":"no","needs_special_setup":"yes","severity_if_unknown":"critical"},"cost_usd":0.000545,"input_tokens":2883,"output_tokens":514,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-025':87C '-2014':18A,21A,74B,176C '-6271':75B,177C '-7169':19A,22A '4.3':41B,85C 'across':158C 'activ':80B 'again':26A 'allow':103C 'apach':140C 'arbitrari':13A 'attack':56B,105C 'bash':6A,12A,28A,29B,39B,83C,163C 'bash43':86C 'boundari':161C 'bourn':3A,9A 'bourne':25A 'bourne-again':2A,8A,24A 'certain':92C 'cgi':30B,133C 'cgid':136C 'client':148C 'code':14A,64B 'command':44B 'craft':118C 'cve':17A,20A,73B,175C 'definit':48B,95C 'demonstr':121C 'dhcp':31B,147C 'environ':50B,61B,100C,119C,156C 'execut':15A,42B,65B,144C,164C 'exist':168C 'exploit':32B,81B 'featur':127C 'file':109C 'fix':70B,173C 'forcecommand':126C 'function':47B,94C 'gnu':1A,7A,23A,38B,82C 'hidden':45B 'host':37B 'http':141C 'impact':115C 'incomplet':69B,172C 'involv':124C 'linux':33B 'list':78B 'malform':93C 'mod':132C,135C 'modul':137C 'note':165C 'occur':157C 'openssh':129C 'possibl':111C 'privileg':160C 'process':88C 'reach':63B 'remot':55B,104C 'runtim':34B 'script':143C 'self':36B 'self-host':35B 'server':142C 'set':59B,154C 'shell':5A,11A,27A 'shellshock':72B 'situat':151C 'sshd':130C 'string':90C 'trail':43B,89C 'unknown':113C 'unspecifi':146C 'valu':52B,98C 'variabl':51B,62B,101C 'vector':123C 'via':116C 'vulner':16A,167C 'write':107C","nicknames":[],"mitigations":[],"who_affected":null,"tier":null,"verified":{},"analyst_revisit_at":null,"first_public_at":"2014-09-25T01:55:04+00:00","kev":{"dateAdded":"2022-01-28","dueDate":"2022-07-28","requiredAction":"Apply updates per vendor instructions.","knownRansomwareCampaignUse":"Unknown"},"cvss_vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","cvss_by":"nvd@nist.gov","poc_count":0,"sources":[{"source":"kev","external_id":"CVE-2014-7169","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2014-7169","severity":null,"published_at":"2022-01-28T00:00:00+00:00","modified_at":null,"first_seen_at":"2026-10-23T19:11:53+00:00","fetched_at":"2026-10-25T16:39:49+00:00","note":null},{"source":"epss","external_id":"CVE-2014-7169","url":"https://api.first.org/data/v1/epss?cve=CVE-2014-7169","severity":null,"published_at":null,"modified_at":null,"first_seen_at":"2026-10-23T19:13:44+00:00","fetched_at":"2026-10-23T19:13:44+00:00","note":null},{"source":"nvd","external_id":"CVE-2014-7169","url":"https://nvd.nist.gov/vuln/detail/CVE-2014-7169","severity":null,"published_at":"2014-09-25T01:55:04+00:00","modified_at":"2026-06-17T00:14:28+00:00","first_seen_at":"2026-10-23T21:57:35+00:00","fetched_at":"2026-10-23T21:57:35+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"}