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TI-2019-07189 Aliases CVE-2019-9803GHSA-6h7p-w66v-f7vw

Origin validation error in Mozilla Firefox

Priority LOW 33CWE-346Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
High
Impact type
Security bypass
Confidentiality · integrity · availability
High · High · None
Fix status
Fixed

Attack profile from CVSS 3.0 · NVD. Fix status from CNA. Impact type from CWE-346.

Summary

The Upgrade-Insecure-Requests (UIR) specification states that if UIR is enabled through Content Security Policy (CSP), navigation to a same-origin URL must be upgraded to HTTPS. Firefox will incorrectly navigate to an HTTP URL rather than perform the security upgrade requested by the CSP in some circumstances, allowing for potential man-in-the-middle attacks on the linked resources. This vulnerability affects Firefox < 66.

Why it matters now

EPSS 0.00559 46th percentileScored 2026-11-07
Fix Fixed Firefox (Mozilla): 66

SSVC decision points

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

Affected products

VendorProductAffected versionsFixed inStatusSource
MozillaFirefoxbefore 6666Patch availableCNA
  • Firefox VendorMozilla Affected before 66 Fixed in 66 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*before 66.0VulnerableMozilla
  • cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:* Versions before 66.0 Vulnerable ·Mozilla

Remediation

  • Fix · CNA Firefox (Mozilla) Fixed in 66

Fixed in the same release

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

  • Release ·

    Mozilla Firefox 66

    21 records Highest priority Priority MEDIUM 10 MEDIUM, 11 LOW

    Other records, highest priority first

    • TI-2019-07177 Type confusion in Mozilla ThunderbirdPriority MEDIUM 61
    • TI-2019-07178 Out-of-bounds write in Mozilla ThunderbirdPriority MEDIUM 57
    • TI-2019-07190 OS command injection in Mozilla FirefoxPriority MEDIUM 46
    Show all 21 records →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2019-9803
  2. 2026-10-03 Alias added: GHSA-6h7p-w66v-f7vw

References

Advisory 4

  • 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