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TI-2018-03687 Aliases CVE-2018-5121GHSA-jcrc-r34f-5gqm

Improper input validation in Mozilla Firefox

Priority LOW 27CWE-20Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · Low · None
Fix status
Fixed

Attack profile from CVSS 3.0 · NVD. Fix status from CNA.

Summary

Low descenders on some Tibetan characters in several fonts on OS X are clipped when rendered in the addressbar. When used as part of an Internationalized Domain Name (IDN) this can be used for domain name spoofing attacks. Note: This attack only affects OS X operating systems. Other operating systems are unaffected. This vulnerability affects Firefox < 58.

Why it matters now

EPSS 0.01441 73rd percentileScored 2026-11-07
Fix Fixed Firefox (Mozilla): 58

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
MozillaFirefoxbefore 5858Patch availableCNA
  • Firefox VendorMozilla Affected before 58 Fixed in 58 Patch available CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*up to 57.0.4VulnerableMozilla
cpe:2.3:o:apple:mac_os_x:*:*:*:*:*:*:*:*all versionsRunning onApple
  • cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:* Versions up to 57.0.4 Vulnerable ·Mozilla
  • cpe:2.3:o:apple:mac_os_x:*:*:*:*:*:*:*:* Versions all versions Running on ·Apple

Remediation

  • Fix · CNA Firefox (Mozilla) Fixed in 58

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    Mozilla Firefox 58

    2 records Highest priority Priority LOW 2 LOW

    Other records, highest priority first

    • TI-2018-03677 Improper input validation in Mozilla FirefoxPriority LOW 27
    Show all 2 records →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2018-5121
  2. 2026-10-03 Alias added: GHSA-jcrc-r34f-5gqm

References

Advisory 1

Other 1

  • TI-2024-08981 Use after free in Mozilla Firefox KEVCVSS 3.1CRITICAL 9.8
  • TI-2022-09832 Use after free in Mozilla Firefox KEVCVSS 3.1CRITICAL 9.6
  • TI-2019-08769 Improper input validation in Mozilla Firefox ESR KEVCVSS 3.1CRITICAL 10.0
  • TI-2010-03577 Mozilla Firefox 3.5.x through 3.5.14 and 3.6.x through 3.6.11, Thunderbird 3.1.6 before… KEVCVSS 3.1CRITICAL 9.8
  • TI-2023-04799 Out-of-bounds write in Google Chrome KEVCVSS 3.1HIGH 8.8
  • TI-2023-04477 Out-of-bounds write in Google Chrome KEVCVSS 3.1HIGH 8.8
See all 3444 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences