CVE-2017-7814
CVE-2017-7814 is a high-severity vulnerability in Mozilla Firefox with a CVSS 3.x base score of 7.8. 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-20.
Key facts
- Severity: High (CVSS 3.x base score 7.8)
- CVSS v2: 6.8
- EPSS exploit prediction: 1% (65th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-20
- Affected product: Mozilla Firefox
- Published:
- Last modified:
Description
File downloads encoded with "blob:" and "data:" URL elements bypassed normal file download checks though the Phishing and Malware Protection feature and its block lists of suspicious sites and files. This would allow malicious sites to lure users into downloading executables that would otherwise be detected as suspicious. This vulnerability affects Firefox < 56, Firefox ESR < 52.4, and Thunderbird < 52.4.
Frequently asked questions
- What is CVE-2017-7814?
- File downloads encoded with "blob:" and "data:" URL elements bypassed normal file download checks though the Phishing and Malware Protection feature and its block lists of suspicious sites and files. This would allow malicious sites to lure users into downloading executables that would otherwise be detected as suspicious. This vulnerability affects Firefox < 56, Firefox ESR < 52.4, and Thunderbird < 52.4.
- How severe is CVE-2017-7814?
- CVE-2017-7814 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2017-7814 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (65th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2017-7814?
- CVE-2017-7814 primarily affects Mozilla Firefox. In total, 14 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2017-7814?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2017-7814 published?
- CVE-2017-7814 was published on 2018-06-11 and last updated on 2026-06-17.
References
- http://www.securityfocus.com/bid/101059
- http://www.securitytracker.com/id/1039465
- https://access.redhat.com/errata/RHSA-2017:2831
- https://access.redhat.com/errata/RHSA-2017:2885
- https://bugzilla.mozilla.org/show_bug.cgi?id=1376036
- https://lists.debian.org/debian-lts-announce/2017/11/msg00000.html
- https://security.gentoo.org/glsa/201803-14
- https://www.debian.org/security/2017/dsa-3987
- https://www.debian.org/security/2017/dsa-4014
- https://www.mozilla.org/security/advisories/mfsa2017-21/
- https://www.mozilla.org/security/advisories/mfsa2017-22/
- https://www.mozilla.org/security/advisories/mfsa2017-23/
Affected products (14)
- 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_eus:7.4:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux_server_eus:7.5:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux_workstation:6.0:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux_workstation:7.0:*:*:*:*:*:*:*
- cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
- cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*
- cpe:2.3:o:debian:debian_linux:7.0:*:*:*:*:*:*:*
- cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
- cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
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-20 (Improper Input Validation) vulnerabilities
- CVE-2026-48316 — Critical (CVSS 10.0): ColdFusion versions 2025.9, 2023.20 and earlier are affected by an Improper Input Validation vulnerability that could…
- CVE-2026-48281 — Critical (CVSS 10.0): ColdFusion versions 2025.9, 2023.20 and earlier are affected by an Improper Input Validation vulnerability that could…
- CVE-2026-48277 — Critical (CVSS 10.0): ColdFusion versions 2025.9, 2023.20 and earlier are affected by an Improper Input Validation vulnerability that could…
- CVE-2026-48055 — Critical (CVSS 10.0): Streambert is a cross-platform Electron Desktop App to stream and download any video media. In versions 2.4.0 and…
- CVE-2026-34910 — Critical (CVSS 10.0): A malicious actor with access to the network could exploit an Improper Input Validation vulnerability found in UniFi OS…
- CVE-2026-33587 — Critical (CVSS 10.0): Lack of user input sanitisation in Open Notebook v1.8.3 allows the application user to execute Python code (and…
Browse all CWE-20 (Improper Input Validation) vulnerabilities →