Mozilla Firefox/Thunderbird/Firefox ESR HTML5 Stream Parser use after free

CVSS Meta Temp Score
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CTI Interest Score
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7.7$0-$5k0.00

Summaryinfo

A vulnerability labeled as critical has been found in Mozilla Firefox, Thunderbird and Firefox ESR. The affected element is an unknown function of the component HTML5 Stream Parser. Such manipulation leads to use after free. This vulnerability is uniquely identified as CVE-2018-18500. The attack can be launched remotely. No exploit exists. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in Mozilla Firefox, Thunderbird and Firefox ESR (Web Browser) (the affected version unknown) and classified as critical. Affected by this issue is an unknown part of the component HTML5 Stream Parser. The manipulation with an unknown input leads to a use after free vulnerability. Using CWE to declare the problem leads to CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. Impacted is confidentiality, integrity, and availability. CVE summarizes:

A use-after-free vulnerability can occur while parsing an HTML5 stream in concert with custom HTML elements. This results in the stream parser object being freed while still in use, leading to a potentially exploitable crash. This vulnerability affects Thunderbird < 60.5, Firefox ESR < 60.5, and Firefox < 65.

The bug was discovered 01/29/2019. The weakness was disclosed 02/05/2019 as MFSA 2019-01 as confirmed security advisory (Website). The advisory is shared for download at mozilla.org. This vulnerability is handled as CVE-2018-18500 since 10/19/2018. The attack may be launched remotely. No form of authentication is required for exploitation. 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 05/08/2020).

The vulnerability was handled as a non-public zero-day exploit for at least 2 days. During that time the estimated underground price was around $25k-$100k. The vulnerability scanner Nessus provides a plugin with the ID 121503 (Scientific Linux Security Update : firefox on SL6.x i386/x86_64 (20190130)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Scientific Linux Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 197358 (Ubuntu Security Notification for Firefox Vulnerabilities (USN-3874-1)).

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

The vulnerability is also documented in the databases at Tenable (121503) and SecurityFocus (BID 91459†). The entries VDB-96101, VDB-96102, VDB-96103 and VDB-96104 are pretty similar. Once again VulDB remains the best source for vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.0
VulDB Meta Temp Score: 7.9

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

NVD Base Score: 9.8
NVD Vector: 🔍

CVSSv2info

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

NVD Base Score: 🔍

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: 121503
Nessus Name: Scientific Linux Security Update : firefox on SL6.x i386/x86_64 (20190130)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

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

Timelineinfo

06/27/2016 🔍
10/19/2018 +844 days 🔍
01/29/2019 +102 days 🔍
01/31/2019 +2 days 🔍
02/05/2019 +5 days 🔍
02/05/2019 +0 days 🔍
02/06/2019 +1 days 🔍
05/08/2020 +457 days 🔍

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Advisory: MFSA 2019-01
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2018-18500 (🔍)
GCVE (CVE): GCVE-0-2018-18500
GCVE (VulDB): GCVE-100-130532
SecurityFocus: 91459 - libical Multiple Heap Overflow Vulnerabilities

See also: 🔍

Entryinfo

Created: 02/06/2019 13:26
Updated: 05/08/2020 11:19
Changes: 02/06/2019 13:26 (69), 05/08/2020 11:19 (11)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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