How severe is CVE-2016-5294?

CVE-2016-5294 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 high, and availability none.

Is CVE-2016-5294 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-2016-5294?

CVE-2016-5294 primarily affects Mozilla Firefox. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2016-5294?

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

When was CVE-2016-5294 published?

CVE-2016-5294 was published on 2018-06-11 and last updated on 2026-06-17.

CVE-2016-5294

CVE-2016-5294 is a medium-severity vulnerability in Mozilla Firefox 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-20.

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-20
Affected product: Mozilla Firefox
Published: 2018-06-11
Last modified: 2026-06-17

Description

The Mozilla Updater can be made to choose an arbitrary target working directory for output files resulting from the update process. This vulnerability requires local system access. Note: this issue only affects Windows operating systems. This vulnerability affects Thunderbird < 45.5, Firefox ESR < 45.5, and Firefox < 50.

Frequently asked questions

What is CVE-2016-5294?: The Mozilla Updater can be made to choose an arbitrary target working directory for output files resulting from the update process. This vulnerability requires local system access. Note: this issue only affects Windows operating systems. This vulnerability affects Thunderbird < 45.5, Firefox ESR < 45.5, and Firefox < 50.
How severe is CVE-2016-5294?: CVE-2016-5294 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 high, and availability none.
Is CVE-2016-5294 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-2016-5294?: CVE-2016-5294 primarily affects Mozilla Firefox. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2016-5294?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2016-5294 published?: CVE-2016-5294 was published on 2018-06-11 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*

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