Patchfirst
CVE-2014-7169 KEVPublic exploit Critical · 9.8 EPSS 99.9%

GNU Bourne-Again Shell (Bash) Arbitrary Code Execution Vulnerability

GNU · Bourne-Again Shell (Bash)

Summary

GNU Bourne-Again Shell (Bash) through 4.3 bash43-025 mishandles trailing strings after certain malformed function definitions in environment variable values, which is an improper neutralization of special elements in OS commands. An attacker with network access and no authentication or user interaction can, by crafting an environment passed across a privilege boundary (for example via OpenSSH sshd ForceCommand, Apache mod_cgi or mod_cgid, or DHCP client scripts), write to files or potentially achieve other unspecified impact.

Official description · NVD

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.

Breakdown
69.9 / 100
Exploited
Yes, in CISA KEV
Reports
0
Tactics
3/15

How an attack unfolds

Based on mappings. Select a step to see the evidence.
  1. How attackers get in

  2. What they do

First seen exploited 5 days after disclosure. Public exploit code (Exploit-DB) was available the same day.

  1. DisclosedPublic exploit codeExploit-DBday 0
  2. First seen exploitedVulnCheck KEV evidence+5 days
  3. Added to CISA KEVEU database agrees+7 yrs

CISA KEV listing is when exploitation was confirmed, not necessarily the first attack.

See the family tree

A fix was bypassed or incomplete 3 times over 6 days.

Same bug familyLinked by evidence that a fix failed or the same code was patched again. Oldest first.

  1. CVE-2014-6271GNU Bourne-Again Shell (Bash) Arbitrary Code Execution24 Sep 2014KEV
  2. incomplete fixHigh

    Why these are linked:

    • Stated in the CVE textNOTE: the original fix for this issue was incorrect; CVE-2014-7169 has been assigned to cover the vulnerability that is still present after the incorrect fix.
    • Stated in the CVE textNOTE: this vulnerability exists because of an incomplete fix for CVE-2014-6271.
    • Similar weakness in the same product (machine-matched)same product + CWE + description similarity
    This CVECVE-2014-7169GNU Bourne-Again Shell (Bash) Arbitrary Code Execution25 Sep 2014KEV
  3. incomplete fixHigh

    Why these are linked:

    • Stated in the CVE textNOTE: this vulnerability exists because of an incomplete fix for CVE-2014-6271 and CVE-2014-7169.
    CVE-2014-6277GNU Bash through 4.3 bash43-026 does not properly parse function…27 Sep 2014
  4. incomplete fixHigh

    Why these are linked:

    • Stated in the CVE textNOTE: this vulnerability exists because of an incomplete fix for CVE-2014-6271, CVE-2014-7169, and CVE-2014-6277.
    CVE-2014-6278GNU Bash OS Command Injection30 Sep 2014KEV

techniques

3 , grouped by in kill-chain order 3

Initial AccessTA0001

External Remote Services T1133 Medium also Persistence
MITRE CTID mapping of the KEV entry · how it is exploited

CVE-2014-7169 allows environment variables set from service/HTTP requests on a serve (e.g. HTTP_COOKIE) in Bash shell that allows for spawning a child shell with the authority/privilege level of the parent shell to perform RCE of code provided by the adversary in the request.

Exploit Public-Facing Application T1190 Medium
MITRE CTID mapping of the KEV entry · how it is exploited

ExecutionTA0002

Unix Shell T1059.004 Medium
MITRE CTID mapping of the KEV entry · primary impact
Lower-confidence links (1)

These come from early or generic mappings, text matching, or contradict this CVE’s details (for example a public-facing technique on a bug that needs a user to open a file). Shown for completeness.

  • Exploitation for Client ExecutionT1203 server-side bug exploitable without user interaction; client-execution technique does not fit

Detection

0 rules for this CVE · 188 general rules for its techniques

Rules for this CVE

0 that reference CVE-2014-7169 directly.

CVE-specific rules are not available in this build. Search SigmaHQ ↗

Sigma rules © SigmaHQ, Detection Rule License 1.1; linked, not reproduced.

What security researchers reported

Not named in any threat report yet

Also mentioned in 50 community threat pulses (AlienVault OTX)

Weaker evidence

Pulses are indicator collections that anyone can publish. A mention is not confirmation of exploitation.

References

161 links, grouped by NVD tag (160 duplicates merged)

Third Party Advisory 62

advisories.mageia.org/MGASA-2014-0393.htmljvn.jp/en/jp/JVN55667175/index.htmljvndb.jvn.jp/jvndb/JVNDB-2014-000126lcamtuf.blogspot.com/2014/09/quick-notes-about-bash-bug-its-impact.htmllinux.oracle.com/errata/ELSA-2014-1306.htmllinux.oracle.com/errata/ELSA-2014-3075.htmllinux.oracle.com/errata/ELSA-2014-3077.htmllinux.oracle.com/errata/ELSA-2014-3078.html
Show 54 moreShow fewerlists.opensuse.org/opensuse-security-announce/2014-09/msg00038.htmllists.opensuse.org/opensuse-security-announce/2014-09/msg00041.htmllists.opensuse.org/opensuse-security-announce/2014-09/msg00042.htmllists.opensuse.org/opensuse-security-announce/2014-09/msg00044.htmllists.opensuse.org/opensuse-security-announce/2014-09/msg00048.htmllists.opensuse.org/opensuse-security-announce/2014-10/msg00004.htmllists.opensuse.org/opensuse-updates/2014-10/msg00023.htmllists.opensuse.org/opensuse-updates/2014-10/msg00025.htmlpacketstormsecurity.com/files/128517/VMware-Security-Advisory-2014-0010.htmlpacketstormsecurity.com/files/128567/CA-Technologies-GNU-Bash-Shellshock.htmlrhn.redhat.com/errata/RHSA-2014-1306.htmlrhn.redhat.com/errata/RHSA-2014-1311.htmlrhn.redhat.com/errata/RHSA-2014-1312.htmlrhn.redhat.com/errata/RHSA-2014-1354.htmlseclists.org/fulldisclosure/2014/Oct/0support.apple.com/kb/HT6495support.novell.com/security/cve/CVE-2014-7169.htmltools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20140926-bashtwitter.com/taviso/statuses/514887394294652929www-01.ibm.com/support/docview.wss?uid=isg3T1021272www-01.ibm.com/support/docview.wss?uid=isg3T1021279www-01.ibm.com/support/docview.wss?uid=isg3T1021361www-01.ibm.com/support/docview.wss?uid=ssg1S1004879www-01.ibm.com/support/docview.wss?uid=ssg1S1004897www-01.ibm.com/support/docview.wss?uid=ssg1S1004898www-01.ibm.com/support/docview.wss?uid=ssg1S1004915www-01.ibm.com/support/docview.wss?uid=swg21685541www-01.ibm.com/support/docview.wss?uid=swg21685604www-01.ibm.com/support/docview.wss?uid=swg21685733www-01.ibm.com/support/docview.wss?uid=swg21685749www-01.ibm.com/support/docview.wss?uid=swg21686084www-01.ibm.com/support/docview.wss?uid=swg21686131www-01.ibm.com/support/docview.wss?uid=swg21686246www-01.ibm.com/support/docview.wss?uid=swg21686445www-01.ibm.com/support/docview.wss?uid=swg21686494www-01.ibm.com/support/docview.wss?uid=swg21687079debian.org/security/2014/dsa-3035novell.com/support/kb/doc.php?id=7015701novell.com/support/kb/doc.php?id=7015721qnap.com/i/en/support/con_show.php?cid=61securityfocus.com/archive/1/533593/100/0/threadedubuntu.com/usn/USN-2363-1ubuntu.com/usn/USN-2363-2vmware.com/security/advisories/VMSA-2014-0010.htmlaccess.redhat.com/articles/1200223access.redhat.com/node/1200223kb.juniper.net/InfoCenter/index?page=content&id=JSA10648support.apple.com/kb/HT6535support.citrix.com/article/CTX200217support.f5.com/kb/en-us/solutions/public/15000/600/sol15629.htmlsupportcenter.checkpoint.com/supportcenter/portal?eventSubmit_doGoviewsolutiondetails=&solutionid=sk102673&src=securityAlertsarista.com/en/support/advisories-notices/security-advisories/1008-security-advisory-0006exploit-db.com/exploits/34879/suse.com/support/shellshock/

Broken Link 64

archives.neohapsis.com/archives/bugtraq/2014-10/0101.htmlsecunia.com/advisories/58200secunia.com/advisories/59272secunia.com/advisories/59737secunia.com/advisories/59907secunia.com/advisories/60024secunia.com/advisories/60034secunia.com/advisories/60044
Show 56 moreShow fewersecunia.com/advisories/60055secunia.com/advisories/60063secunia.com/advisories/60193secunia.com/advisories/60325secunia.com/advisories/60433secunia.com/advisories/60947secunia.com/advisories/61065secunia.com/advisories/61128secunia.com/advisories/61129secunia.com/advisories/61188secunia.com/advisories/61283secunia.com/advisories/61287secunia.com/advisories/61291secunia.com/advisories/61312secunia.com/advisories/61313secunia.com/advisories/61328secunia.com/advisories/61442secunia.com/advisories/61471secunia.com/advisories/61479secunia.com/advisories/61485secunia.com/advisories/61503secunia.com/advisories/61550secunia.com/advisories/61552secunia.com/advisories/61565secunia.com/advisories/61603secunia.com/advisories/61618secunia.com/advisories/61619secunia.com/advisories/61622secunia.com/advisories/61626secunia.com/advisories/61633secunia.com/advisories/61641secunia.com/advisories/61643secunia.com/advisories/61654secunia.com/advisories/61676secunia.com/advisories/61700secunia.com/advisories/61703secunia.com/advisories/61711secunia.com/advisories/61715secunia.com/advisories/61780secunia.com/advisories/61816secunia.com/advisories/61855secunia.com/advisories/61857secunia.com/advisories/61873secunia.com/advisories/62228secunia.com/advisories/62312secunia.com/advisories/62343www-01.ibm.com/support/docview.wss?uid=swg21685914www-01.ibm.com/support/docview.wss?uid=swg21686447www-01.ibm.com/support/docview.wss?uid=swg21686479www-947.ibm.com/support/entry/portal/docdisplay?lndocid=MIGR-5096315mandriva.com/security/advisories?name=MDVSA-2015:164help.ecostruxureit.com/display/public/UADCO8x/StruxureWare+Data+Center+Operation+Software+Vulnerability+Fixeskb.bluecoat.com/index?page=content&id=SA82kc.mcafee.com/corporate/index?page=content&id=SB10085support.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-c04497075support.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-c04518183
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