CVE-2018-5138: mozilla firefox Improper Input Validation
Vulnerability summary
CVE-2018-5138 is a medium (CVSS 5.3) Improper Input Validation vulnerability in mozilla firefox. EPSS estimates a 1.09% chance of exploitation in the next 30 days, higher than 64.7% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 2 · Related 2Timeline
- 11-06-2018PublishedVulnerability first disclosed.
- 05-08-2024Last modifiedVulnerability information updated.
Description
A spoofing vulnerability can occur when a malicious site with an extremely long domain name is opened in an Android Custom Tab (a browser panel inside another app) and the default browser is Firefox for Android. This could allow an attacker to spoof which page is actually loaded and in use. Note: this issue only affects Firefox for Android. Other versions and operating systems are unaffected. This vulnerability affects Firefox < 59.
CVSS metrics
2 scores · 1 source · 2 versionsEPSS trend
Probability
1.09%
Chance of exploitation in the next 30 days
Percentile
65%
Versus all other CVEs
30-day change
-0.02 pp
From 1.11% on 18-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Mozilla1 product
- firefox≥ unspecified, < 59 | < 59.0
1 vendor · 1 product