Mozilla Firefox ReadableByteStreams use after free

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.4$5k-$25k0.00

Summaryinfo

A vulnerability described as critical has been identified in Mozilla Firefox. This vulnerability affects the function ReadableByteStreams. Executing a manipulation can lead to use after free. This vulnerability appears as CVE-2023-6207. The attack may be performed from remote. There is no available exploit. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability classified as critical was found in Mozilla Firefox (Web Browser) (unknown version). This vulnerability affects the function ReadableByteStreams. The manipulation with an unknown input leads to a use after free vulnerability. The CWE definition for the vulnerability is CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

Ownership mismanagement led to a use-after-free in ReadableByteStreams This vulnerability affects Firefox < 120, Firefox < 115.5, and Thunderbird < 115.5.0.

The weakness was presented 11/21/2023. The advisory is shared for download at bugzilla.mozilla.org. This vulnerability was named CVE-2023-6207 since 11/20/2023. Successful exploitation requires user interaction by the victim. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $5k-$25k (estimation calculated on 06/19/2025).

The vulnerability scanner Nessus provides a plugin with the ID 239860 (TencentOS Server 2: firefox (TSSA-2023:0316)), 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 (239860). 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: 7.6
VulDB Meta Temp Score: 7.4

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

NVD Base Score: 8.8
NVD Vector: 🔍

CVSSv2info

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

Exploitinginfo

Class: Use after free
CWE: CWE-416 / 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: 239860
Nessus Name: TencentOS Server 2: firefox (TSSA-2023:0316)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Timelineinfo

11/20/2023 🔍
11/21/2023 +1 days 🔍
11/21/2023 +0 days 🔍
06/19/2025 +576 days 🔍

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Advisory: DLA 3661-1
Status: Confirmed

CVE: CVE-2023-6207 (🔍)
GCVE (CVE): GCVE-0-2023-6207
GCVE (VulDB): GCVE-100-245908

Entryinfo

Created: 11/21/2023 16:14
Updated: 06/19/2025 14:53
Changes: 11/21/2023 16:14 (38), 12/15/2023 11:03 (1), 12/15/2023 11:10 (11), 06/19/2025 14:53 (17)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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