CVE-2026-94422: Authentication Bypass by Spoofing
CVE-2026-94422 is a high-severity vulnerability in xdg-dbus-proxy versions before 0.1.9 that allows an attacker to bypass message filtering on the D-Bus session bus. This flaw arises from incorrect message filtering implementation, enabling a malicious or compromised Flatpak application to set a reply serial number on non-reply messages. Exploiting this can lead to arbitrary code execution outside the Flatpak sandbox, compromising the sandbox boundary. The vulnerability also affects other app frameworks using xdg-dbus-proxy, such as Firejail.
AI Analysis
Technical Summary
An authentication bypass vulnerability exists in xdg-dbus-proxy prior to version 0.1.9 due to improper message filtering on the D-Bus session bus. Specifically, attackers can set a reply serial number on messages that are not replies, circumventing the intended filtering mechanism. This flaw allows malicious or compromised Flatpak applications to execute arbitrary code outside their sandbox environment. Since xdg-dbus-proxy is used as part of the sandbox boundary for Flatpak and other frameworks like Firejail, this vulnerability undermines sandbox isolation.
Potential Impact
Successful exploitation allows attackers, including malicious or compromised Flatpak applications, to bypass sandbox restrictions and execute arbitrary code outside the sandbox. This compromises system integrity and confidentiality, potentially leading to full system compromise. The vulnerability has a high CVSS score of 8.8, reflecting its critical impact on confidentiality, integrity, and availability.
Mitigation Recommendations
A fix is available in xdg-dbus-proxy version 0.1.9 and later. Users and administrators should upgrade to version 0.1.9 or newer to remediate this vulnerability. No other mitigation guidance is provided, and patching is the recommended action.
CVE-2026-94422: Authentication Bypass by Spoofing
Description
CVE-2026-94422 is a high-severity vulnerability in xdg-dbus-proxy versions before 0.1.9 that allows an attacker to bypass message filtering on the D-Bus session bus. This flaw arises from incorrect message filtering implementation, enabling a malicious or compromised Flatpak application to set a reply serial number on non-reply messages. Exploiting this can lead to arbitrary code execution outside the Flatpak sandbox, compromising the sandbox boundary. The vulnerability also affects other app frameworks using xdg-dbus-proxy, such as Firejail.
CVSS v3.1
Score 8.8high
Affected software
pkg:github/flatpak/xdg-dbus-proxyRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
An authentication bypass vulnerability exists in xdg-dbus-proxy prior to version 0.1.9 due to improper message filtering on the D-Bus session bus. Specifically, attackers can set a reply serial number on messages that are not replies, circumventing the intended filtering mechanism. This flaw allows malicious or compromised Flatpak applications to execute arbitrary code outside their sandbox environment. Since xdg-dbus-proxy is used as part of the sandbox boundary for Flatpak and other frameworks like Firejail, this vulnerability undermines sandbox isolation.
Potential Impact
Successful exploitation allows attackers, including malicious or compromised Flatpak applications, to bypass sandbox restrictions and execute arbitrary code outside the sandbox. This compromises system integrity and confidentiality, potentially leading to full system compromise. The vulnerability has a high CVSS score of 8.8, reflecting its critical impact on confidentiality, integrity, and availability.
Mitigation Recommendations
A fix is available in xdg-dbus-proxy version 0.1.9 and later. Users and administrators should upgrade to version 0.1.9 or newer to remediate this vulnerability. No other mitigation guidance is provided, and patching is the recommended action.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- redhat
- Date Reserved
- 2026-09-21T15:32:06.674Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Gcve Source
- db.gcve.eu
Threat ID: 6abfee7da43b0b3b89e543bf
Added to database: 10/02/2026, 17:48:45 UTC
Last enriched: 10/02/2026, 17:54:16 UTC
Last updated: 10/02/2026, 23:05:57 UTC
Views: 3
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