CVE-2026-100779 - Vulnerability Details - OpenCVE

Use-after-free in the XSLT component. This vulnerability was fixed in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17.

No CVSS v4.0

No CVSS v3.1

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Key SSVC decision points have not yet been added.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

Mozilla

Firefox

affected

Version	Status	Constraints
`115.42`	unaffected	≤ 115.*
`140.17`	unaffected	≤ 140.*
`153.4`	unaffected	≤ 153.*
`157`	unaffected	≤ *

No data.

No data.

No data.

Project Subscriptions

No data.

Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References

Link	Providers
https://bugzilla.mozilla.org/show_bug.cgi?id=2068417
https://www.mozilla.org/security/advisories/mfsa2026-100/
https://www.mozilla.org/security/advisories/mfsa2026-97/
https://www.mozilla.org/security/advisories/mfsa2026-98/
https://www.mozilla.org/security/advisories/mfsa2026-99/

History

Tue, 29 Sep 2026 13:15:00 +0000

Type	Values Removed	Values Added
Description		Use-after-free in the XSLT component. This vulnerability was fixed in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17.
Title		Use-after-free in the XSLT component
References		https://bugzilla.mozilla.org/show_bug.cgi?id=2068417 https://www.mozilla.org/security/advisories/mfsa2026-100/ https://www.mozilla.org/security/advisories/mfsa2026-97/ https://www.mozilla.org/security/advisories/mfsa2026-98/ https://www.mozilla.org/security/advisories/mfsa2026-99/

Projects

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MITRE

Status: PUBLISHED

Assigner: mozilla

Published: 2026-09-29T12:36:06.174Z

Updated: 2026-09-29T14:49:15.527Z

Reserved: 2026-09-26T19:16:50.745Z

Link: CVE-2026-100779

Vulnrichment

No data.

NVD

Status : Received

Published: 2026-09-29T13:17:42.690

Modified: 2026-09-29T13:17:42.690

Link: CVE-2026-100779

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

No weakness.

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