Mozilla Firefox up to 150 Popup Blocker clickjacking

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.8$5k-$25k0.00

Summaryinfo

A vulnerability has been found in Mozilla Firefox up to 150 and classified as problematic. This vulnerability affects unknown code of the component Popup Blocker. This manipulation causes an unknown weakness. This vulnerability is registered as CVE-2026-8964. Remote exploitation of the attack is possible. No exploit is available. The affected component should be upgraded.

Detailsinfo

A vulnerability has been found in Mozilla Firefox up to 150 and classified as problematic. Affected by this vulnerability is an unknown part of the component Popup Blocker. The CWE definition for the vulnerability is CWE-451. The user interface (UI) does not properly represent critical information to the user, allowing the information - or its source - to be obscured or spoofed. This is often a component in phishing attacks. As an impact it is known to affect integrity. The summary by CVE is:

Spoofing issue in the Popup Blocker component. This vulnerability was fixed in Firefox 151 and Thunderbird 151.

It is possible to read the advisory at bugzilla.mozilla.org. This vulnerability is known as CVE-2026-8964 since 05/19/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. It demands that the victim is doing some kind of user interaction. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 06/17/2026). The attack technique deployed by this issue is T1566.003 according to MITRE ATT&CK.

The vulnerability scanner Nessus provides a plugin with the ID 316438 (Linux Distros Unpatched Vulnerability : CVE-2026-8964), 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 (316438), EUVD (EUVD-2026-30915) and CERT Bund (WID-SEC-2026-1606). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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: 5.9
VulDB Meta Temp Score: 5.8

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

ADP CISA Base Score: 7.5
ADP CISA Vector: 🔒

CVSSv2info

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

Exploitinginfo

Class: Clickjacking
CWE: CWE-451
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: 316438
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-8964

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-2026-8964 (🔒)
GCVE (CVE): GCVE-0-2026-8964
GCVE (VulDB): GCVE-100-364675
EUVD: 🔒
CERT Bund: WID-SEC-2026-1606 - Mozilla Firefox und Thunderbird: Mehrere Schwachstellen

Entryinfo

Created: 05/19/2026 15:56
Updated: 06/17/2026 19:43
Changes: 05/19/2026 15:56 (54), 05/19/2026 21:34 (1), 05/23/2026 13:39 (14), 05/23/2026 19:14 (2), 06/17/2026 19:43 (7)
Complete: 🔍
Cache ID: 216::103

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

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