CVE-2026-25740
Privilege Escalation via CAP_NET_RAW in Captive Browser
Publication date: 2026-02-09
Last updated on: 2026-02-09
Assigner: GitHub, Inc.
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| nixos | captive_browser | to 25.11 (exc) |
| nixos | captive_browser | 25.11 |
| nixos | captive_browser | 26.05 |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-250 | The product performs an operation at a privilege level that is higher than the minimum level required, which creates new weaknesses or amplifies the consequences of other weaknesses. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
This vulnerability exists in the captive browser, a dedicated Chrome instance used to log into captive portals without changing DNS settings. In versions 25.05 and earlier, when the programs.captive-browser feature is enabled, any user on the system can execute arbitrary commands with the CAP_NET_RAW capability. This capability allows binding to privileged ports and spoofing localhost traffic from privileged services, which can lead to unauthorized actions.
The issue is fixed in versions 25.11 and 26.05.
How can this vulnerability impact me? :
This vulnerability can allow any user on the affected system to run arbitrary commands with elevated network privileges (CAP_NET_RAW). This means an attacker could bind to privileged network ports or spoof traffic from trusted local services, potentially leading to unauthorized network access, data interception, or manipulation of network communications.
How does this vulnerability affect compliance with common standards and regulations (like GDPR, HIPAA)?:
I don't know
How can this vulnerability be detected on my network or system? Can you suggest some commands?
I don't know
What immediate steps should I take to mitigate this vulnerability?
To mitigate this vulnerability, upgrade the captive browser to version 25.11 or later, as the issue is fixed in versions 25.11 and 26.05.
Additionally, if possible, disable the programs.captive-browser feature until the upgrade is applied to prevent users from exploiting the CAP_NET_RAW capability.