Vulnerability · Published Feb 9, 2026 · Assigned by GitHub_M

CVE-2026-25740Privilege escalation to the `CAP_NET_RAW` capability via the `programs.captive-browser` NixOS module

Medium 5.8

In plain English

A medium-severity security flaw in nixpkgs from NixOS. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 6% of all known vulnerabilities).

Severity (CVSS 4.0)5.8Medium

Exploit odds (30 days)0.2%top 94.3% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

captive browser, a dedicated Chrome instance to log into captive portals without messing with DNS settings. In 25.05 and earlier, when programs.captive-browser is enabled, any user of the system can run arbitrary commands with the CAP_NET_RAW capability (binding to privileged ports, spoofing localhost traffic from privileged services...). This vulnerability is fixed in 25.11 and 26.05.

Affected products (as reported)

Vendor	Product	Versions
NixOS	nixpkgs	<= 25.05

Weakness: CWE-250 · Vector: CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N

References

https://github.com/NixOS/nixpkgs/security/advisories/GHSA-wc3r-c66x-8xmc x_refsource_CONFIRM
https://github.com/NixOS/nixpkgs/pull/487775 x_refsource_MISC
https://github.com/NixOS/nixpkgs/pull/487779 x_refsource_MISC