// For flags

CVE-2021-23997

Ubuntu Security Notice USN-4926-1

Severity Score

8.8
*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

-
*SSVC
Descriptions

Due to unexpected data type conversions, a use-after-free could have occurred when interacting with the font cache. We presume that with enough effort this could have been exploited to run arbitrary code. This vulnerability affects Firefox < 88.

Debido a conversiones inesperadas de tipos de datos, podría haberse producido un uso de memoria previamente liberada al interactuar con la caché de fuentes. Presumimos que con suficiente esfuerzo esto podría haber sido explotado para ejecutar código arbitrario. Esta vulnerabilidad afecta a Firefox versiones anteriores a 88

Multiple security issues were discovered in Firefox. If a user were tricked into opening a specially crafted website, an attacker could potentially exploit these to cause a denial of service, spoof the browser UI, bypass security restrictions, trick the user into disclosing confidential information, or execute arbitrary code. Various other issues were also addressed.

*Credits: N/A
CVSS Scores
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
Attack Vector
Network
Attack Complexity
Medium
Authentication
None
Confidentiality
Partial
Integrity
Partial
Availability
Partial
* Common Vulnerability Scoring System
SSVC
  • Decision:-
Exploitation
-
Automatable
-
Tech. Impact
-
* Organization's Worst-case Scenario
Timeline
  • 2021-01-13 CVE Reserved
  • 2021-04-27 CVE Published
  • 2024-08-03 CVE Updated
  • 2025-03-30 EPSS Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
  • CWE-681: Incorrect Conversion between Numeric Types
CAPEC
References (1)
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Mozilla
Search vendor "Mozilla"
Firefox
Search vendor "Mozilla" for product "Firefox"
< 88.0
Search vendor "Mozilla" for product "Firefox" and version " < 88.0"
-
Affected