CVE-2018-5142
CVE-2018-5142 is a medium-severity vulnerability in Mozilla Firefox with a CVSS 3.x base score of 5.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.
Key facts
- Severity: Medium (CVSS 3.x base score 5.3)
- CVSS v2: 5.0
- EPSS exploit prediction: 1% (65th percentile)
- Actively exploited: Not listed in CISA KEV
- Affected product: Mozilla Firefox
- Published:
- Last modified:
Description
If Media Capture and Streams API permission is requested from documents with "data:" or "blob:" URLs, the permission notifications do not properly display the originating domain. The notification states "Unknown protocol" as the requestee, leading to user confusion about which site is asking for this permission. This vulnerability affects Firefox < 59.
Frequently asked questions
- What is CVE-2018-5142?
- If Media Capture and Streams API permission is requested from documents with "data:" or "blob:" URLs, the permission notifications do not properly display the originating domain. The notification states "Unknown protocol" as the requestee, leading to user confusion about which site is asking for this permission. This vulnerability affects Firefox < 59.
- How severe is CVE-2018-5142?
- CVE-2018-5142 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
- Is CVE-2018-5142 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-2018-5142?
- CVE-2018-5142 primarily affects Mozilla Firefox. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2018-5142?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2018-5142 published?
- CVE-2018-5142 was published on 2018-06-11 and last updated on 2026-06-17.
References
- http://www.securityfocus.com/bid/103386
- http://www.securitytracker.com/id/1040514
- https://bugzilla.mozilla.org/show_bug.cgi?id=1366357
- https://usn.ubuntu.com/3596-1/
- https://www.mozilla.org/security/advisories/mfsa2018-06/
Affected products (4)
- cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
- cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:*
- cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:*
- cpe:2.3:o:canonical:ubuntu_linux:17.10:*:*:*:*:*:*:*
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