CVE-2016-0634

The expansion of '\h' in the prompt string in bash 4.3 allows remote authenticated users to execute arbitrary code via shell metacharacters placed in 'hostname' of a machine.

Published: 2017-08-28 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2016-0634 is rated Moderate Risk (62.3/100): CVSS High severity, with high exploitation likelihood (EPSS 6.02%, 92th percentile). EPSS ranks this CVE among the most likely to be exploited in the near term. High exploitation likelihood—assess exposure and prioritize remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2016-0634

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-26 6.07% 6.02% -0.05%
2 2026-06-15 3.69% 6.07% +2.38%
3 2026-05-30 — 3.69% —

Full EPSS history (22 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2016-0634

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.0 HIGH
CVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.6 5.9 [email protected]
6.0 2.0 MEDIUM
AV:N/AC:M/Au:S/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:S)
A single authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 6.8 6.4 [email protected]

Weakness enumeration for CVE-2016-0634

OS Trackers for CVE-2016-0634

vendor priority summary link
alpine — CVE-2016-0634: 1 source package rows (bash); 10 state rows across 10 repos (3.10-main, 3.11-main, 3.12-main, 3.17-main, 3.18-main, 3.19-main, 3.20-main, 3.21-main, 3.22-main, edge-main); fixed 10, open 0. https://security.alpinelinux.org/vuln/CVE-2016-0634
debian unimportant CVE-2016-0634 unimportant priority: Debian including 1 source packages (bash), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2016-0634
gentoo normal CVE-2016-0634: 1 GLSA(s) (201612-39), 1 atom(s) (app-shells/bash); latest impact normal. https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2016-0634
redhat medium — https://access.redhat.com/security/cve/CVE-2016-0634
suse low CVE-2016-0634 severity low: SUSE including 67 source package names (0.9.1:bash-4.3-83.10.1, 0.9.1:libreadline6-6.3-83.10.1, …), 207 product×package rows across 70 product lines (Container caasp/v4/default-http-backend, Container caasp/v4/dnsmasq-nanny, … (70 product lines)): Fixed 207. https://www.suse.com/security/cve/CVE-2016-0634/
ubuntu low CVE-2016-0634 low priority: Ubuntu including 1 source packages (bash), 14 status rows across 14 suites (artful, bionic, cosmic, disco, eoan, focal, groovy, hirsute, precise, trusty, upstream, xenial, yakkety, zesty): not-affected 9, released 4, ignored 1. https://ubuntu.com/security/CVE-2016-0634

Affected software / configurations for CVE-2016-0634

Vendor Product Version Raw CPE
gnu bash 4.3 cpe:2.3:a:gnu:bash:4.3:*:*:*:*:*:*:*

References for CVE-2016-0634

URL Tags
http://rhn.redhat.com/errata/RHSA-2017-0725.html
http://www.openwall.com/lists/oss-security/2016/09/16/12 Mailing List Third Party Advisory
http://www.openwall.com/lists/oss-security/2016/09/16/8 Mailing List Patch Third Party Advisory
http://www.openwall.com/lists/oss-security/2016/09/18/11 Mailing List Third Party Advisory
http://www.openwall.com/lists/oss-security/2016/09/19/7 Mailing List Third Party Advisory
http://www.openwall.com/lists/oss-security/2016/09/20/1 Mailing List Third Party Advisory
http://www.openwall.com/lists/oss-security/2016/09/27/9 Mailing List Third Party Advisory
http://www.openwall.com/lists/oss-security/2016/09/29/27 Mailing List Third Party Advisory
http://www.openwall.com/lists/oss-security/2016/10/07/6 Mailing List Third Party Advisory
http://www.openwall.com/lists/oss-security/2016/10/10/3 Mailing List Third Party Advisory
http://www.openwall.com/lists/oss-security/2016/10/10/4 Mailing List Third Party Advisory
http://www.securityfocus.com/bid/92999 Third Party Advisory VDB Entry
https://access.redhat.com/errata/RHSA-2017:1931
https://bugzilla.redhat.com/show_bug.cgi?id=1377613 Issue Tracking Patch Third Party Advisory VDB Entry
https://security.gentoo.org/glsa/201612-39 Third Party Advisory
cvelogic Threat Intelligence