CVE-2021-23977 - Vulnerability Details - OpenCVE

Description

Firefox for Android suffered from a time-of-check-time-of-use vulnerability that allowed a malicious application to read sensitive data from application directories. Note: This issue is only affected Firefox for Android. Other operating systems are unaffected. This vulnerability affects Firefox < 86.

Published: 2021-02-26

Score: 5.3 Medium

EPSS: < 1% Very Low

KEV: No

Impact:

Action:

Analysis

No analysis available yet.

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
`< 86`	affected	—

Configuration 1 [-]

cpe:2.3:a:mozilla:firefox:*:*:*:*:*:android:*:*

No data.

No data available yet.

Remediation

No remediation available yet.

Tracking

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Advisories

Source	ID	Title
EUVD	EUVD-2021-10898	Firefox for Android suffered from a time-of-check-time-of-use vulnerability that allowed a malicious application to read sensitive data from application directories. Note: This issue is only affected Firefox for Android. Other operating systems are unaffected. This vulnerability affects Firefox < 86.

No CVSS v4.0

Attack Vector Network

Attack Complexity High

Privileges Required None

Scope Unchanged

Confidentiality Impact High

Integrity Impact None

Availability Impact None

User Interaction Required

No CVSS v3.0

Access Vector Network

Access Complexity High

Authentication None

Confidentiality Impact Partial

Integrity Impact None

Availability Impact None

This CVE is not in the KEV list.

The EPSS score is 0.00874.

Key SSVC decision points have not yet been added.

References

Link	Providers
https://bugzilla.mozilla.org/show_bug.cgi?id=1684761
https://security.gentoo.org/glsa/202104-10
https://www.mozilla.org/security/advisories/mfsa2021-07/

History

No history.

Subscriptions

Mozilla Firefox

MITRE

Status: PUBLISHED

Assigner: mozilla

Published: 2021-02-26T02:13:06.000Z

Updated: 2024-08-03T19:14:10.022Z

Reserved: 2021-01-13T00:00:00.000Z

Link: CVE-2021-23977

Vulnrichment

No data.

NVD

Status : Modified

Published: 2021-02-26T03:15:14.213

Modified: 2026-06-17T03:39:05.970

Link: CVE-2021-23977

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-367
Time-of-check Time-of-use (TOCTOU) Race Condition

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