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TI-2023-05698 Aliases CVE-2023-6204GHSA-c9gw-j4mh-mj26

Out-of-bounds read in Mozilla Firefox

Priority LOW 30CWE-125Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Required
Attack complexity
Low
Impact type
Information disclosure
Confidentiality · integrity · availability
High · None · None
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-125 and the CVSS impact.

Summary

On some systems—depending on the graphics settings and drivers—it was possible to force an out-of-bounds read and leak memory data into the images created on the canvas element. This vulnerability affects Firefox < 120, Firefox ESR < 115.5.0, and Thunderbird < 115.5.

Why it matters now

EPSS 0.00841 58th 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

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

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-2023-05706 Out-of-bounds write in Mozilla FirefoxPriority MEDIUM 42
    • 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
    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-2023-05706 Out-of-bounds write in Mozilla FirefoxPriority MEDIUM 42
    • 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
    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-2023-6204
  2. 2026-10-03 Alias added: GHSA-c9gw-j4mh-mj26

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