CVE-2026-74977

Analyzed Analyzed - Analysis Complete

Integer Overflow in Firefox Graphics Component

Publication date: 2026-08-18

Last updated on: 2026-08-25

Assigner: Mozilla Corporation

Description

Integer overflow in the Graphics component. This vulnerability was fixed in Firefox 154, Firefox ESR 153.1, Thunderbird 154, and Thunderbird 153.1.

CVSS Scores

EPSS Scores

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Meta Information

Published

2026-08-18

Last Modified

2026-08-25

Generated

2026-09-08

AI Q&A

2026-08-18

EPSS Evaluated

2026-09-06

NVD

CVE-2026-74977

EUVD

EUVD-2026-60690

Affected Vendors & Products

Vendor	Product	Version / Range
mozilla	firefox	to 153.1.0 (exc)
mozilla	thunderbird	to 153.1.0 (exc)

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-190	The product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.

Attack-Flow Graph

Executive Summary

This vulnerability is an integer overflow in Firefox's Graphics component. An integer overflow occurs when a calculation produces a result larger than the maximum value that can be stored in the variable's data type, potentially leading to unexpected behavior or crashes.

Detection Guidance

This vulnerability is specific to Firefox versions before 154 and Firefox ESR before 153.1. To detect it, check your installed Firefox version with commands like 'firefox --version' or 'apt show firefox' (Linux) or via 'Help > About Firefox' (GUI). If the version is below 154 or ESR below 153.1, the system is vulnerable.

Impact Analysis

An attacker could exploit this to cause application crashes or execute arbitrary code, potentially leading to data loss or unauthorized system access. Users running vulnerable Firefox versions are at risk.

Compliance Impact

This vulnerability does not directly impact compliance with GDPR, HIPAA, or similar standards as it is a technical flaw in the Graphics component of Firefox and Thunderbird. Compliance depends on implementation and mitigation measures rather than the vulnerability itself.

Mitigation Strategies

Update Firefox to version 154 or Firefox ESR to version 153.1 or later to address the integer overflow in the Graphics component.

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