Mozilla Firefox up to 116 JIT UpdateRegExpStatics memory corruption

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.3$5k-$25k0.00

Summaryinfo

A vulnerability was found in Mozilla Firefox up to 116. It has been classified as problematic. This impacts the function UpdateRegExpStatics of the component JIT. The manipulation leads to memory corruption. This vulnerability is listed as CVE-2023-4577. The attack may be initiated remotely. There is no available exploit. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in Mozilla Firefox up to 116 (Web Browser). This issue affects the function UpdateRegExpStatics of the component JIT. The manipulation with an unknown input leads to a memory corruption vulnerability. Using CWE to declare the problem leads to 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. Impacted is availability.

The weakness was presented 08/29/2023 by Lukas Bernhard as Bug 1847397 as confirmed advisory (Website). The advisory is shared at bugzilla.mozilla.org. The advisory contains:

When UpdateRegExpStatics attempted to access initialStringHeap it could already have been garbage collected prior to entering the function, which could potentially have led to an exploitable crash.
The identification of this vulnerability is CVE-2023-4577. It demands that the victim is doing some kind of user interaction. Technical details are known, but no exploit is available. The price for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 06/20/2025).

The vulnerability scanner Nessus provides a plugin with the ID 239763 (TencentOS Server 4: thunderbird (TSSA-2024:0450)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 117 eliminates this vulnerability. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (239763). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

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Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.4
VulDB Meta Temp Score: 5.3

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.5
NVD Vector: 🔍

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: 239763
Nessus Name: TencentOS Server 4: thunderbird (TSSA-2024:0450)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Upgrade: Firefox 117

Timelineinfo

08/29/2023 🔍
08/29/2023 +0 days 🔍
08/29/2023 +0 days 🔍
08/30/2023 +1 days 🔍
06/20/2025 +660 days 🔍

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Advisory: Bug 1847397
Researcher: Lukas Bernhard
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2023-4577 (🔍)
GCVE (CVE): GCVE-0-2023-4577
GCVE (VulDB): GCVE-100-238313

Entryinfo

Created: 08/30/2023 14:23
Updated: 06/20/2025 19:42
Changes: 08/30/2023 14:23 (17), 08/30/2023 14:26 (30), 09/22/2023 17:13 (2), 09/22/2023 17:20 (11), 06/20/2025 19:42 (17)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Discussion

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