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TI-2017-05384 Aliases CVE-2017-7764GHSA-mc3w-fw7x-qrw7

Improper input validation in Mozilla Firefox

Priority LOW 28CWE-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 and Red Hat.

Summary

Characters from the "Canadian Syllabics" unicode block can be mixed with characters from other unicode blocks in the addressbar instead of being rendered as their raw "punycode" form, allowing for domain name spoofing attacks through character confusion. The current Unicode standard allows characters from "Aspirational Use Scripts" such as Canadian Syllabics to be mixed with Latin characters in the "moderately restrictive" IDN profile. We have changed Firefox behavior to match the upcoming Unicode version 10.0 which removes this category and treats them as "Limited Use Scripts.". This vulnerability affects Firefox < 54, Firefox ESR < 52.2, and Thunderbird < 52.2.

Why it matters now

EPSS 0.01962 80th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed Firefox (Mozilla): 54Firefox ESR (Mozilla): 52.2+1 more productRed Hat: 2 advisories

SSVC decision points

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

Affected products

VendorProductAffected versionsFixed inStatusSource
MozillaFirefoxbefore 5454Patch availableCNA
MozillaFirefox ESRbefore 52.252.2Patch availableCNA
MozillaThunderbirdbefore 52.252.2Patch availableCNA
  • Firefox VendorMozilla Affected before 54 Fixed in 54 Patch available CNA
  • Firefox ESR VendorMozilla Affected before 52.2 Fixed in 52.2 Patch available CNA
  • Thunderbird VendorMozilla Affected before 52.2 Fixed in 52.2 Patch available CNA

CPE configurations NVD · 4

CPEVersionsRoleVendor
cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*before 52.2.0; before 54.0VulnerableMozilla
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*before 52.2.0VulnerableMozilla
cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*8.0VulnerableDebian
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*9.0VulnerableDebian
  • cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:* Versions before 52.2.0; before 54.0 Vulnerable ·Mozilla
  • cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:* Versions before 52.2.0 Vulnerable ·Mozilla
  • cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:* Versions 8.0 Vulnerable ·Debian
  • cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* Versions 9.0 Vulnerable ·Debian

Remediation

  • Fix · CNA Firefox (Mozilla) Fixed in 54
  • Fix · CNA Firefox ESR (Mozilla) Fixed in 52.2
  • Fix · CNA Thunderbird (Mozilla) Fixed in 52.2

Red Hat 2 advisories

  • RHSA-2017:1561 Released 2017-06-21 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux Client (v. 7) thunderbird-52.2.0-1.el7_3
    • Red Hat Enterprise Linux Desktop (v. 6) thunderbird-52.2.0-1.el6_9
    • Red Hat Enterprise Linux Server Optional (v. 6) thunderbird-52.2.0-1.el6_9
    • Red Hat Enterprise Linux Server Optional (v. 7) thunderbird-52.2.0-1.el7_3
    • Red Hat Enterprise Linux Workstation (v. 6) thunderbird-52.2.0-1.el6_9
    • Red Hat Enterprise Linux Workstation (v. 7) thunderbird-52.2.0-1.el7_3
  • RHSA-2017:1440 Released 2017-06-14 · Red Hat rating Critical
    firefox security update
    • Red Hat Enterprise Linux Client (v. 7) firefox-52.2.0-1.el7_3
    • Red Hat Enterprise Linux Client Optional (v. 7) firefox-52.2.0-1.el7_3
    • Red Hat Enterprise Linux Desktop (v. 6) firefox-52.2.0-1.el6_9
    • Red Hat Enterprise Linux Desktop Optional (v. 6) firefox-52.2.0-1.el6_9
    • Red Hat Enterprise Linux HPC Node Optional (v. 6) firefox-52.2.0-1.el6_9
    • Red Hat Enterprise Linux Server (v. 6) firefox-52.2.0-1.el6_9
    • Red Hat Enterprise Linux Server (v. 7) firefox-52.2.0-1.el7_3
    • Red Hat Enterprise Linux Server Optional (v. 6) firefox-52.2.0-1.el6_9, firefox-52.2.0-1.el6_9.ppc
    • Red Hat Enterprise Linux Server Optional (v. 7) firefox-52.2.0-1.el7_3, firefox-52.2.0-1.el7_3.ppc
    • Red Hat Enterprise Linux Workstation (v. 6) firefox-52.2.0-1.el6_9
    • Red Hat Enterprise Linux Workstation (v. 7) firefox-52.2.0-1.el7_3
    • Red Hat Enterprise Linux Workstation Optional (v. 6) firefox-52.2.0-1.el6_9
    • Red Hat Enterprise Linux Workstation Optional (v. 7) firefox-52.2.0-1.el7_3

Fixed in the same release

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

  • Advisory ·

    Mozilla Firefox, Firefox ESR, Thunderbird — RHSA-2017:1440

    12 records Highest priority Priority MEDIUM 10 MEDIUM, 2 LOW

    Other records, highest priority first

    • TI-2017-05396 Memory corruption in Mozilla FirefoxPriority MEDIUM 50
    • TI-2017-05377 Use after free in Mozilla FirefoxPriority MEDIUM 47
    • TI-2017-05376 Use after free in Mozilla FirefoxPriority MEDIUM 47
    Show all 12 records → Advisory →
  • Advisory ·

    Mozilla Firefox, Firefox ESR, Thunderbird — RHSA-2017:1561

    12 records Highest priority Priority MEDIUM 10 MEDIUM, 2 LOW

    Other records, highest priority first

    • TI-2017-05396 Memory corruption in Mozilla FirefoxPriority MEDIUM 50
    • TI-2017-05377 Use after free in Mozilla FirefoxPriority MEDIUM 47
    • TI-2017-05376 Use after free in Mozilla FirefoxPriority MEDIUM 47
    Show all 12 records → Advisory →
Show 2 more groups
  • Advisory ·

    Mozilla Firefox, Firefox ESR, Thunderbird — DSA-3881

    12 records Highest priority Priority MEDIUM 10 MEDIUM, 2 LOW

    Other records, highest priority first

    • TI-2017-05396 Memory corruption in Mozilla FirefoxPriority MEDIUM 50
    • TI-2017-05377 Use after free in Mozilla FirefoxPriority MEDIUM 47
    • TI-2017-05376 Use after free in Mozilla FirefoxPriority MEDIUM 47
    Show all 12 records → Advisory →
  • Advisory ·

    Mozilla Firefox, Firefox ESR, Thunderbird — DSA-3918

    12 records Highest priority Priority MEDIUM 10 MEDIUM, 2 LOW

    Other records, highest priority first

    • TI-2017-05396 Memory corruption in Mozilla FirefoxPriority MEDIUM 50
    • TI-2017-05377 Use after free in Mozilla FirefoxPriority MEDIUM 47
    • TI-2017-05376 Use after free in Mozilla FirefoxPriority MEDIUM 47
    Show all 12 records → Advisory →

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux Client (v. 7)Fixed RHSA-2017:1440, RHSA-2017:1561
Red Hat Enterprise Linux Client Optional (v. 7)Fixed RHSA-2017:1440
Red Hat Enterprise Linux Desktop (v. 6)Fixed RHSA-2017:1440, RHSA-2017:1561
Red Hat Enterprise Linux Desktop Optional (v. 6)Fixed RHSA-2017:1440
Red Hat Enterprise Linux HPC Node Optional (v. 6)Fixed RHSA-2017:1440
Red Hat Enterprise Linux Server (v. 6)Fixed RHSA-2017:1440
Red Hat Enterprise Linux Server (v. 7)Fixed RHSA-2017:1440
Red Hat Enterprise Linux Server Optional (v. 6)Fixed RHSA-2017:1440, RHSA-2017:1561
Red Hat Enterprise Linux Server Optional (v. 7)Fixed RHSA-2017:1440, RHSA-2017:1561
Red Hat Enterprise Linux Workstation (v. 6)Fixed RHSA-2017:1440, RHSA-2017:1561
Red Hat Enterprise Linux Workstation (v. 7)Fixed RHSA-2017:1440, RHSA-2017:1561
Red Hat Enterprise Linux Workstation Optional (v. 6)Fixed RHSA-2017:1440
Red Hat Enterprise Linux Workstation Optional (v. 7)Fixed RHSA-2017:1440

Timeline

  1. 2026-10-02 Threatist record created from CVE-2017-7764
  2. 2026-10-03 Alias added: GHSA-mc3w-fw7x-qrw7

References

Exploit 1

Advisory 8

  • 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