Mozilla Firefox/Firefox ESR/Thunderbird Garbage Collection memory corruption

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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4.1$0-$5k0.00

Summaryinfo

A vulnerability categorized as critical has been discovered in Mozilla Firefox, Firefox ESR and Thunderbird. The impacted element is an unknown function of the component Garbage Collection. The manipulation results in memory corruption. This vulnerability is identified as CVE-2021-29984. The attack can be executed remotely. There is not any exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, was found in Mozilla Firefox, Firefox ESR and Thunderbird (Web Browser) (affected version unknown). Affected is an unknown functionality of the component Garbage Collection. The manipulation with an unknown input leads to a memory corruption vulnerability. CWE is classifying the issue as 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. This is going to have an impact on availability.

The weakness was released 08/18/2021. The advisory is shared for download at mozilla.org. This vulnerability is traded as CVE-2021-29984. 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 $0-$5k (estimation calculated on 08/18/2025).

The vulnerability scanner Nessus provides a plugin with the ID 249817 (Linux Distros Unpatched Vulnerability : CVE-2021-29984), which helps to determine the existence of the flaw in a target environment.

Upgrading eliminates this vulnerability. The upgrade is hosted for download at mozilla.org.

The vulnerability is also documented in the vulnerability database at Tenable (249817). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

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Vendor

Name

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.3
VulDB Meta Temp Score: 4.1

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
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: 249817
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2021-29984

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: mozilla.org

Timelineinfo

04/01/2021 🔍
08/18/2021 +139 days 🔍
08/18/2021 +0 days 🔍
08/18/2025 +1461 days 🔍

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Advisory: mozilla.org
Status: Confirmed

CVE: CVE-2021-29984 (🔍)
GCVE (CVE): GCVE-0-2021-29984
GCVE (VulDB): GCVE-100-181056

Entryinfo

Created: 08/18/2021 10:27
Updated: 08/18/2025 11:59
Changes: 08/18/2021 10:27 (39), 08/19/2021 23:01 (2), 08/18/2025 11:59 (16)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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