CVE-2021-23976

HIGH
8.1
CVSS Score
Published: February 26, 2021 at 01:48 AM UTC
Updated: June 17, 2026 at 03:39 AM UTC
1 product affected across 1 vendorFirefox

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Severity
HIGH8.1
Exploit prediction
EPSS 1%

Description

When accepting a malicious intent from other installed apps, Firefox for Android accepted manifests from arbitrary file paths and allowed declaring webapp manifests for other origins. This could be used to gain fullscreen access for UI spoofing and could also lead to cross-origin attacks on targeted websites. Note: This issue is a different issue from CVE-2020-26954 and only affected Firefox for Android. Other operating systems are unaffected. This vulnerability affects Firefox < 86.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 86v < 86.0
Affected range stops below 86, so it looks safe — our inference, not a vendor statement
Affected range stops below 86.0, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (3)

x_refsource_MISCIssue TrackingPermissions RequiredVendor Advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1684627
Vendor Advisoryx_refsource_GENTOOThird Party Advisory
https://security.gentoo.org/glsa/202104-10
x_refsource_MISCRelease NotesVendor Advisory
https://www.mozilla.org/security/advisories/mfsa2021-07/

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
NONE
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-1021

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