How severe is CVE-2016-9401?

CVE-2016-9401 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2016-9401 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (34th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2016-9401?

CVE-2016-9401 primarily affects Gnu Bash. In total, 22 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2016-9401?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2016-9401 published?

CVE-2016-9401 was published on 2017-01-23 and last updated on 2026-06-17.

CVE-2016-9401

CVE-2016-9401 is a medium-severity vulnerability in Gnu Bash with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-416.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
CVSS v2: 2.1
EPSS exploit prediction: 0% (34th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-416
Affected product: Gnu Bash
Published: 2017-01-23
Last modified: 2026-06-17

Description

popd in bash might allow local users to bypass the restricted shell and cause a use-after-free via a crafted address.

Frequently asked questions

What is CVE-2016-9401?: popd in bash might allow local users to bypass the restricted shell and cause a use-after-free via a crafted address.
How severe is CVE-2016-9401?: CVE-2016-9401 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2016-9401 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (34th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-9401?: CVE-2016-9401 primarily affects Gnu Bash. In total, 22 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2016-9401?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2016-9401 published?: CVE-2016-9401 was published on 2017-01-23 and last updated on 2026-06-17.

References

Affected products (22)

cpe:2.3:a:gnu:bash:*:*:*:*:*:*:*:*
cpe:2.3:a:gnu:bash:4.4:patch1:*:*:*:*:*:*
cpe:2.3:a:gnu:bash:4.4:patch2:*:*:*:*:*:*
cpe:2.3:a:gnu:bash:4.4:patch3:*:*:*:*:*:*
cpe:2.3:a:gnu:bash:4.4:patch4:*:*:*:*:*:*
cpe:2.3:a:gnu:bash:4.4:patch5:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_desktop:6.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_desktop:7.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server:6.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server:7.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server_aus:7.4:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server_aus:7.6:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server_aus:7.7:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server_eus:7.4:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server_eus:7.5:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server_eus:7.6:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server_eus:7.7:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server_tus:7.6:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server_tus:7.7:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_workstation:6.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_workstation:7.0:*:*:*:*:*:*:*

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