Mozilla Firefox up to 150 Networking cross-domain policy

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.6$5k-$25k0.00

Summaryinfo

A vulnerability categorized as problematic has been discovered in Mozilla Firefox up to 150. Impacted is an unknown function of the component Networking Component. Executing a manipulation can lead to cross-domain policy. This vulnerability is handled as CVE-2026-8948. The attack can be executed remotely. There is not any exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability has been found in Mozilla Firefox up to 150 and classified as problematic. This vulnerability affects an unknown functionality of the component Networking Component. The manipulation with an unknown input leads to a cross-domain policy vulnerability. The CWE definition for the vulnerability is CWE-942. The product uses a cross-domain policy file that includes domains that should not be trusted. As an impact it is known to affect integrity. CVE summarizes:

Same-origin policy bypass in the DOM: Networking component. This vulnerability was fixed in Firefox 151 and Thunderbird 151.

The advisory is available at bugzilla.mozilla.org. This vulnerability was named CVE-2026-8948 since 05/19/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. Successful exploitation requires user interaction by the victim. The technical details are unknown and an exploit is not available. The structure of the vulnerability defines a possible price range of USD $5k-$25k at the moment (estimation calculated on 06/17/2026).

The vulnerability scanner Nessus provides a plugin with the ID 315434 (Mozilla Thunderbird < 151.0), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 151 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (315434) and CERT Bund (WID-SEC-2026-1606). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Affected

  • Debian Linux
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • SUSE Linux
  • Oracle Linux
  • IGEL OS
  • SUSE openSUSE
  • RESF Rocky Linux
  • Mozilla Firefox
  • Mozilla Firefox ESR
  • Mozilla Thunderbird

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.7
VulDB Meta Temp Score: 6.6

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

ADP CISA Base Score: 9.1
ADP CISA Vector: 🔒

CVSSv2info

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

Exploitinginfo

Class: Cross-domain policy
CWE: CWE-942 / CWE-346 / CWE-345
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: 315434
Nessus Name: Mozilla Thunderbird < 151.0

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Firefox 151

Timelineinfo

05/19/2026 Advisory disclosed
05/19/2026 +0 days CVE reserved
05/19/2026 +0 days VulDB entry created
06/17/2026 +29 days VulDB entry last update

Sourcesinfo

Vendor: mozilla.org
Product: mozilla.org

Advisory: bugzilla.mozilla.org
Status: Confirmed

CVE: CVE-2026-8948 (🔒)
GCVE (CVE): GCVE-0-2026-8948
GCVE (VulDB): GCVE-100-364666
CERT Bund: WID-SEC-2026-1606 - Mozilla Firefox und Thunderbird: Mehrere Schwachstellen

Entryinfo

Created: 05/19/2026 15:55
Updated: 06/17/2026 13:24
Changes: 05/19/2026 15:55 (55), 05/20/2026 05:15 (2), 05/23/2026 11:52 (12), 05/27/2026 08:33 (7), 06/17/2026 13:24 (1)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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