01 Record

CVE-2026-4689

Sandbox escape due to incorrect boundary conditions, integer overflow in the XPCOM component

CriticalPUBLISHEDCNA: mozilla

CNA base score10.0 CVSS v3.xCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

View raw JSON

02 Description

Sandbox escape due to incorrect boundary conditions, integer overflow in the XPCOM component

03 Exploitation and scoring

Exploitation

Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.

SSVC decision

ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
Technical ImpacttotalSuccessful exploitation gives total control of the vulnerable component.

CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.

EPSS probability

0.66% probability of exploitation activity in the next 30 days.

EPSS percentile

Ranks above 49.2% of scored records. A rank, not a probability.

NVD base score

10.0 (CVSS v3.x), scored by the NVD independently of the CNA.

NVD CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

NVD analysis status

Modified. NVD last modified this record on 2026-07-15.

Red Hat severity

Important. Red Hat's rating for its own products, not a CVSS rating.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

04 Metadata

Published

2026-03-24 12:30Z5 MO AGO

Last updated

2026-07-15 00:49Z1 MO AGO

Reserved

2026-03-23

Assigning CNA

mozilla

Record state

PUBLISHED

Severity

Critical (CVSS 10.0)

CNA CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

Weaknesses

CWE-120Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')Base
CWE-190Integer Overflow or WraparoundBase
CWE-754Improper Check for Unusual or Exceptional ConditionsClass

Data version

5.2

Document digest

117747248bc78188e9ffabf110fc5c2bd9a9229b3a750b1164e4445bd58f5bb2

05 Affected products

VendorProductVersionsPlatforms

MozillaFirefoxNot specified—

MozillaThunderbirdNot specified—

06 References

bugzilla.mozilla.orghttps://bugzilla.mozilla.org/show_bug.cgi?id=2016374
www.mozilla.orghttps://www.mozilla.org/security/advisories/mfsa2026-20/
www.mozilla.orghttps://www.mozilla.org/security/advisories/mfsa2026-21/
www.mozilla.orghttps://www.mozilla.org/security/advisories/mfsa2026-22/
www.mozilla.orghttps://www.mozilla.org/security/advisories/mfsa2026-23/
www.mozilla.orghttps://www.mozilla.org/security/advisories/mfsa2026-24/
access.redhat.comhttps://access.redhat.com/security/cve/CVE-2026-4689vdb-entryx_refsource_REDHAT
bugzilla.redhat.comRHBZ#2450718https://bugzilla.redhat.com/show_bug.cgi?id=2450718issue-trackingx_refsource_REDHAT
security.access.redhat.comhttps://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-4689.jsonx_sadp-csaf-vex
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:8427vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:7843vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:8315vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:5931vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:6342vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:5932vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:6917vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:7840vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:8285vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:7858vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:8850vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:7842vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:8289vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:7838vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:8288vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:7839vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:8286vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:7841vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:8287vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:7845vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:8290vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:7837vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:8284vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:5930vendor-advisoryx_refsource_REDHAT
access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:6188vendor-advisoryx_refsource_REDHAT

01 Record index

CVE-2026-4689

02 Description

03 Exploitation and scoring

04 Metadata

05 Affected products

06 References

02 Records

CVE-2026-4689

02 Description

03 Exploitation and scoring

04 Metadata

05 Affected products

06 References