How severe is CVE-2017-5397?

CVE-2017-5397 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2017-5397 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (87th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2017-5397?

CVE-2017-5397 affects Mozilla Firefox. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2017-5397?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2017-5397 published?

CVE-2017-5397 was published on 2018-06-11 and last updated on 2026-06-17.

CVE-2017-5397

CVE-2017-5397 is a critical-severity vulnerability in Mozilla Firefox with a CVSS 3.x base score of 9.8. 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-829.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 10.0
EPSS exploit prediction: 3% (87th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-829
Affected product: Mozilla Firefox
Published: 2018-06-11
Last modified: 2026-06-17

Description

The cache directory on the local file system is set to be world writable. Firefox defaults to extracting libraries from this cache. This allows for the possibility of an installed malicious application or tools with write access to the file system to replace files used by Firefox with their own versions. This vulnerability affects Firefox < 51.0.3.

Frequently asked questions

What is CVE-2017-5397?: The cache directory on the local file system is set to be world writable. Firefox defaults to extracting libraries from this cache. This allows for the possibility of an installed malicious application or tools with write access to the file system to replace files used by Firefox with their own versions. This vulnerability affects Firefox < 51.0.3.
How severe is CVE-2017-5397?: CVE-2017-5397 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2017-5397 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (87th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2017-5397?: CVE-2017-5397 affects Mozilla Firefox. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2017-5397?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2017-5397 published?: CVE-2017-5397 was published on 2018-06-11 and last updated on 2026-06-17.

References

Affected products (1)

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

More vulnerabilities in Mozilla Firefox

CVE-2026-4725 — Critical (CVSS 10.0): Sandbox escape due to use-after-free in the Graphics: Canvas2D component. This vulnerability was fixed in Firefox 149…
CVE-2026-4692 — Critical (CVSS 10.0): Sandbox escape in the Responsive Design Mode component. This vulnerability was fixed in Firefox 149, Firefox ESR…
CVE-2026-4689 — Critical (CVSS 10.0): Sandbox escape due to incorrect boundary conditions, integer overflow in the XPCOM component. This vulnerability was…
CVE-2026-4688 — Critical (CVSS 10.0): Sandbox escape due to use-after-free in the Disability Access APIs component. This vulnerability was fixed in Firefox…
CVE-2026-2778 — Critical (CVSS 10.0): Sandbox escape due to incorrect boundary conditions in the DOM: Core & HTML component. This vulnerability was fixed in…
CVE-2026-2776 — Critical (CVSS 10.0): Sandbox escape due to incorrect boundary conditions in the Telemetry component in External Software. This vulnerability…

All CVEs affecting Mozilla Firefox →

Other CWE-829 vulnerabilities

CVE-2026-1699 — Critical (CVSS 10.0): In the Eclipse Theia Website repository, the GitHub Actions workflow .github/workflows/preview.yml used…
CVE-2025-70974 — Critical (CVSS 10.0): Fastjson before 1.2.48 mishandles autoType because, when an @type key is in a JSON document, and the value of that key…
CVE-2025-0982 — Critical (CVSS 10.0): Sandbox escape in the JavaScript Task feature of Google Cloud Application Integration allows an actor to execute…
CVE-2021-41037 — Critical (CVSS 10.0): In Eclipse p2, installable units are able to alter the Eclipse Platform installation and the local machine via…
CVE-2022-1161 — Critical (CVSS 10.0): An attacker with the ability to modify a user program may change user program code on some ControlLogix, CompactLogix,…
CVE-2020-4561 — Critical (CVSS 10.0): IBM Cognos Analytics 11.0 and 11.1 DQM API allows submitting of all control requests in unauthenticated sessions. This…

Browse all CWE-829 vulnerabilities →