Mozilla Firefox/Firefox ESR/Thunderbird memory corruption

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.0$5k-$25k0.00

Summaryinfo

A vulnerability, which was classified as critical, was found in Mozilla Firefox, Firefox ESR and Thunderbird. This affects an unknown function. Executing a manipulation can lead to memory corruption. This vulnerability appears as CVE-2021-38493. The attack may be performed from remote. There is no available exploit. You should upgrade the affected component.

Detailsinfo

A vulnerability has been found in Mozilla Firefox, Firefox ESR and Thunderbird (Web Browser) (affected version not known) and classified as critical. This vulnerability affects some unknown functionality. The manipulation with an unknown input leads to a memory corruption vulnerability. The CWE definition for the vulnerability is CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. As an impact it is known to affect confidentiality, integrity, and availability.

The weakness was presented 11/03/2021. The advisory is shared for download at mozilla.org. This vulnerability was named CVE-2021-38493 since 08/10/2021. Successful exploitation requires user interaction by the victim. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $5k-$25k (estimation calculated on 01/21/2026).

The vulnerability scanner Nessus provides a plugin with the ID 294772 (MiracleLinux 7 : firefox-78.14.0-1.0.1.el7.AXS7 (AXSA:2021-2415:25)), which helps to determine the existence of the flaw in a target environment.

Upgrading eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (294772). Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

Vendor

Name

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.0

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Memory corruption
CWE: CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 294772
Nessus Name: MiracleLinux 7 : firefox-78.14.0-1.0.1.el7.AXS7 (AXSA:2021-2415:25)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Timelineinfo

08/10/2021 🔍
11/03/2021 +85 days 🔍
11/03/2021 +0 days 🔍
01/21/2026 +1540 days 🔍

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Advisory: mozilla.org
Status: Confirmed

CVE: CVE-2021-38493 (🔍)
GCVE (CVE): GCVE-0-2021-38493
GCVE (VulDB): GCVE-100-185908

Entryinfo

Created: 11/03/2021 06:54
Updated: 01/21/2026 10:51
Changes: 11/03/2021 06:54 (38), 11/05/2021 05:06 (1), 01/21/2026 10:51 (16)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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