Mozilla Firefox/Thunderbird up to 91.0 HTTP3 Header request smuggling

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.0$0-$5k0.00

Summaryinfo

A vulnerability identified as critical has been detected in Mozilla Firefox and Thunderbird up to 91.0. Impacted is an unknown function of the component HTTP3 Header Handler. This manipulation causes request smuggling. This vulnerability is handled as CVE-2021-29991. The attack can be initiated remotely. There is not any exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability has been found in Mozilla Firefox and Thunderbird up to 91.0 (Web Browser) and classified as critical. Affected by this vulnerability is some unknown functionality of the component HTTP3 Header Handler. The manipulation with an unknown input leads to a request smuggling vulnerability. The CWE definition for the vulnerability is CWE-444. The product acts as an intermediary HTTP agent (such as a proxy or firewall) in the data flow between two entities such as a client and server, but it does not interpret malformed HTTP requests or responses in ways that are consistent with how the messages will be processed by those entities that are at the ultimate destination. As an impact it is known to affect confidentiality, integrity, and availability.

The weakness was released 11/03/2021. It is possible to read the advisory at mozilla.org. This vulnerability is known as CVE-2021-29991 since 04/01/2021. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 11/06/2021).

Upgrading to version 91.0.1 eliminates this vulnerability. The upgrade is hosted for download at mozilla.org.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.2
VulDB Meta Temp Score: 7.0

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

NVD Base Score: 8.1
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Request smuggling
CWE: CWE-444
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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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Firefox/Thunderbird 91.0.1

Timelineinfo

04/01/2021 🔍
11/03/2021 +216 days 🔍
11/03/2021 +0 days 🔍
11/06/2021 +3 days 🔍

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Advisory: mozilla.org
Status: Confirmed

CVE: CVE-2021-29991 (🔍)
GCVE (CVE): GCVE-0-2021-29991
GCVE (VulDB): GCVE-100-185971

Entryinfo

Created: 11/03/2021 09:57
Updated: 11/06/2021 18:18
Changes: 11/03/2021 09:57 (41), 11/06/2021 18:10 (1), 11/06/2021 18:18 (18)
Complete: 🔍
Cache ID: 216::103

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