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TI-2023-05706 Aliases CVE-2023-6212GHSA-4cv2-qh42-x2j4

Out-of-bounds write in Mozilla Firefox

Priority MEDIUM 42CWE-787Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Required
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 19 fixed, 1 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-787 and the CVSS impact.

Summary

Memory safety bugs present in Firefox 119, Firefox ESR 115.4, and Thunderbird 115.4. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects Firefox < 120, Firefox ESR < 115.5.0, and Thunderbird < 115.5.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00947 61st percentileScored 2026-11-07
Fix Partial Firefox (Mozilla): 120Firefox ESR (Mozilla): 115.5.0+1 more productRed Hat: 20 advisoriesRed Hat: 19 fixed, 1 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
MozillaFirefoxbefore 120120Patch availableCNA
MozillaFirefox ESRbefore 115.5.0115.5.0Patch availableCNA
MozillaThunderbirdbefore 115.5115.5Patch availableCNA
  • Firefox VendorMozilla Affected before 120 Fixed in 120 Patch available CNA
  • Firefox ESR VendorMozilla Affected before 115.5.0 Fixed in 115.5.0 Patch available CNA
  • Thunderbird VendorMozilla Affected before 115.5 Fixed in 115.5 Patch available CNA

CPE configurations NVD · 6

CPEVersionsRoleVendor
cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*before 120.0VulnerableMozilla
cpe:2.3:a:mozilla:firefox_esr:*:*:*:*:*:*:*:*before 115.5.0VulnerableMozilla
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*before 115.5VulnerableMozilla
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*10.0VulnerableDebian
cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*11.0VulnerableDebian
cpe:2.3:o:debian:debian_linux:12.0:*:*:*:*:*:*:*12.0VulnerableDebian
  • cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:* Versions before 120.0 Vulnerable ·Mozilla
  • cpe:2.3:a:mozilla:firefox_esr:*:*:*:*:*:*:*:* Versions before 115.5.0 Vulnerable ·Mozilla
  • cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:* Versions before 115.5 Vulnerable ·Mozilla
  • cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:* Versions 10.0 Vulnerable ·Debian
  • cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:* Versions 11.0 Vulnerable ·Debian
  • cpe:2.3:o:debian:debian_linux:12.0:*:*:*:*:*:*:* Versions 12.0 Vulnerable ·Debian

Remediation

  • Fix · CNA Firefox (Mozilla) Fixed in 120
  • Fix · CNA Firefox ESR (Mozilla) Fixed in 115.5.0
  • Fix · CNA Thunderbird (Mozilla) Fixed in 115.5

Red Hat 20 advisories

  • RHSA-2023:7577 Released 2023-11-29 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream EUS (v.9.2) firefox-115.5.0-1.el9_2, firefox-x11-115.5.0-1.el9_2
  • RHSA-2023:7574 Released 2023-11-29 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream AUS (v. 8.2) thunderbird-115.5.0-1.el8_2
    • Red Hat Enterprise Linux AppStream E4S (v. 8.2) thunderbird-115.5.0-1.el8_2
    • Red Hat Enterprise Linux AppStream TUS (v. 8.2) thunderbird-115.5.0-1.el8_2
  • RHSA-2023:7573 Released 2023-11-29 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream AUS (v. 8.2) firefox-115.5.0-1.el8_2
    • Red Hat Enterprise Linux AppStream E4S (v. 8.2) firefox-115.5.0-1.el8_2
    • Red Hat Enterprise Linux AppStream TUS (v. 8.2) firefox-115.5.0-1.el8_2
Show 17 more Red Hat advisories
  • RHSA-2023:7569 Released 2023-11-29 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream AUS (v.8.4) firefox-115.5.0-1.el8_4
    • Red Hat Enterprise Linux AppStream E4S (v.8.4) firefox-115.5.0-1.el8_4
    • Red Hat Enterprise Linux AppStream TUS (v.8.4) firefox-115.5.0-1.el8_4
  • RHSA-2023:7570 Released 2023-11-29 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream AUS (v.8.4) thunderbird-115.5.0-1.el8_4
    • Red Hat Enterprise Linux AppStream E4S (v.8.4) thunderbird-115.5.0-1.el8_4
    • Red Hat Enterprise Linux AppStream TUS (v.8.4) thunderbird-115.5.0-1.el8_4
  • RHSA-2023:7547 Released 2023-11-28 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream E4S (v. 8.1) firefox-115.5.0-1.el8_1
  • RHSA-2023:7512 Released 2023-11-27 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream EUS (v.8.6) firefox-115.5.0-1.el8_6
  • RHSA-2023:7509 Released 2023-11-27 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux Client (v. 7) firefox-115.5.0-1.el7_9
    • Red Hat Enterprise Linux Client Optional (v. 7) firefox-115.5.0-1.el7_9
    • Red Hat Enterprise Linux Server (v. 7) firefox-115.5.0-1.el7_9
    • Red Hat Enterprise Linux Server Optional (v. 7) firefox-115.5.0-1.el7_9
    • Red Hat Enterprise Linux Workstation (v. 7) firefox-115.5.0-1.el7_9
    • Red Hat Enterprise Linux Workstation Optional (v. 7) firefox-115.5.0-1.el7_9
  • RHSA-2023:7505 Released 2023-11-27 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux Client (v. 7) thunderbird-115.5.0-1.el7_9
    • Red Hat Enterprise Linux Server Optional (v. 7) thunderbird-115.5.0-1.el7_9
    • Red Hat Enterprise Linux Workstation (v. 7) thunderbird-115.5.0-1.el7_9
  • RHSA-2023:7508 Released 2023-11-27 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream (v. 8) firefox-115.5.0-1.el8_9
  • RHSA-2023:7507 Released 2023-11-27 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream (v. 9) firefox-115.5.0-1.el9_3, firefox-x11-115.5.0-1.el9_3
  • RHSA-2023:7511 Released 2023-11-27 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream EUS (v.8.8) firefox-115.5.0-1.el8_8
  • RHSA-2023:7506 Released 2023-11-27 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream EUS (v.9.0) thunderbird-115.5.0-1.el9_0
  • RHSA-2023:7510 Released 2023-11-27 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream EUS (v.9.0) firefox-115.5.0-1.el9_0
  • RHSA-2023:7503 Released 2023-11-27 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream EUS (v.8.6) thunderbird-115.5.0-1.el8_6
  • RHSA-2023:7504 Released 2023-11-27 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream EUS (v.8.8) thunderbird-115.5.0-1.el8_8
  • RHSA-2023:7500 Released 2023-11-27 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream (v. 8) thunderbird-115.5.0-1.el8_9
  • RHSA-2023:7501 Released 2023-11-27 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream (v. 9) thunderbird-115.5.0-1.el9_3
  • RHSA-2023:7499 Released 2023-11-27 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream EUS (v.9.2) thunderbird-115.5.0-1.el9_2
  • RHSA-2023:7502 Released 2023-11-27 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream E4S (v. 8.1) thunderbird-115.5.0-1.el8_1

Fixed in the same release

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

  • Release ·

    Mozilla Firefox 120

    10 records Highest priority Priority MEDIUM 3 MEDIUM, 7 LOW

    Other records, highest priority first

    • TI-2023-05702 When using X11, text selected by the page using the Selection API was erroneously copied…Priority MEDIUM 40
    • TI-2023-05701 Use after free in Mozilla FirefoxPriority MEDIUM 40
    • TI-2023-05707 Out-of-bounds write in Mozilla FirefoxPriority LOW 39
    Show all 10 records →
  • Release ·

    Mozilla Firefox ESR, Thunderbird 115.5, 115.5.0

    7 records Highest priority Priority MEDIUM 3 MEDIUM, 4 LOW

    Other records, highest priority first

    • TI-2023-05702 When using X11, text selected by the page using the Selection API was erroneously copied…Priority MEDIUM 40
    • TI-2023-05701 Use after free in Mozilla FirefoxPriority MEDIUM 40
    • TI-2023-05703 Path traversal in Mozilla FirefoxPriority LOW 32
    Show all 7 records →

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux AppStream (v. 8)Fixed RHSA-2023:7500, RHSA-2023:7508
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2023:7501, RHSA-2023:7507
Red Hat Enterprise Linux AppStream AUS (v. 8.2)Fixed RHSA-2023:7573, RHSA-2023:7574
Red Hat Enterprise Linux AppStream AUS (v.8.4)Fixed RHSA-2023:7569, RHSA-2023:7570
Red Hat Enterprise Linux AppStream E4S (v. 8.1)Fixed RHSA-2023:7502, RHSA-2023:7547
Red Hat Enterprise Linux AppStream E4S (v. 8.2)Fixed RHSA-2023:7573, RHSA-2023:7574
Red Hat Enterprise Linux AppStream E4S (v.8.4)Fixed RHSA-2023:7569, RHSA-2023:7570
Red Hat Enterprise Linux AppStream EUS (v.8.6)Fixed RHSA-2023:7503, RHSA-2023:7512
Red Hat Enterprise Linux AppStream EUS (v.8.8)Fixed RHSA-2023:7504, RHSA-2023:7511
Red Hat Enterprise Linux AppStream EUS (v.9.0)Fixed RHSA-2023:7506, RHSA-2023:7510
Red Hat Enterprise Linux AppStream EUS (v.9.2)Fixed RHSA-2023:7499, RHSA-2023:7577
Red Hat Enterprise Linux AppStream TUS (v. 8.2)Fixed RHSA-2023:7573, RHSA-2023:7574
Red Hat Enterprise Linux AppStream TUS (v.8.4)Fixed RHSA-2023:7569, RHSA-2023:7570
Red Hat Enterprise Linux Client (v. 7)Fixed RHSA-2023:7505, RHSA-2023:7509
Red Hat Enterprise Linux Client Optional (v. 7)Fixed RHSA-2023:7509
Red Hat Enterprise Linux Server (v. 7)Fixed RHSA-2023:7509
Red Hat Enterprise Linux Server Optional (v. 7)Fixed RHSA-2023:7505, RHSA-2023:7509
Red Hat Enterprise Linux Workstation (v. 7)Fixed RHSA-2023:7505, RHSA-2023:7509
Red Hat Enterprise Linux Workstation Optional (v. 7)Fixed RHSA-2023:7509

Timeline

  1. 2026-10-02 Threatist record created from CVE-2023-6212
  2. 2026-10-03 Alias added: GHSA-4cv2-qh42-x2j4

References

Advisory 4

Other 3

  • 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