CVE-2018-5117

Severity: medium (CVSS 5.3 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2018-06-11 · updated 2026-06-17

Description

If right-to-left text is used in the addressbar with left-to-right alignment, it is possible in some circumstances to scroll this text to spoof the displayed URL. This issue could result in the wrong URL being displayed as a location, which can mislead users to believe they are on a different site than the one loaded. This vulnerability affects Thunderbird < 52.6, Firefox ESR < 52.6, and Firefox < 58.

Affected products

Canonical Ubuntu Linux: 14.04, 16.04, 17.10
Debian Linux: 7.0, 8.0, 9.0
Mozilla Firefox: before 58.0; before 52.6.0 — fixed in 52.6.0, 58.0
Mozilla Thunderbird: before 52.6.0 — fixed in 52.6.0
Red Hat Enterprise Linux: 6.0, 7.0
RedHat Enterprise Linux Desktop: 6.0, 7.0
RedHat Enterprise Linux Server: 6.0, 7.0
RedHat Enterprise Linux Server Aus: 7.3, 7.4
RedHat Enterprise Linux Server Eus: 7.3, 7.4, 7.5
RedHat Enterprise Linux Workstation: 6.0, 7.0

How to fix

Upgrade to a fixed version: Mozilla Firefox 52.6.0, 58.0; Mozilla Thunderbird 52.6.0. Check the vendor advisory for mitigations.

References

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