UBUNTU-CVE-2026-42177

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Source

https://ubuntu.com/security/CVE-2026-42177

Import Source

https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-42177.json

JSON Data

https://api.osv.dev/v1/vulns/UBUNTU-CVE-2026-42177

Upstream

CVE-2026-42177

Published

2026-05-12T18:17:00Z

Modified

2026-05-27T19:15:07.217497657Z

Severity

5.3 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:N CVSS Calculator
Ubuntu - medium

Summary

[none]

Details

linux-entra-sso is a browser plugin for Linux to SSO on Microsoft Entra ID. Prior to 1.8.1, platform/chrome/js/platform-chrome.js:69-88 registers a single declarativeNetRequest rule whose urlFilter is Platform.SSOURL + "/", i.e. "https://login.microsoftonline.com/". Chrome's urlFilter without a | or || anchor is substring-matched against the full request URL. The same applied rule action is modifyHeaders that attaches the Entra ID Primary Refresh Token cookie. The Firefox adapter in platform/firefox/js/platform-firefox.js:53 performs a belt-and-braces startsWith(Platform.SSOURL) check before injecting the header; the Chrome adapter does not. When the extension holds broad host permissions through the optionalhostpermissions: ["https:///"] declared in platform/chrome/manifest.json:34, a main-frame navigation to a URL whose path embeds https://login.microsoftonline.com/ causes Chrome to attach the PRT cookie to the request to the attacker-controlled host. This vulnerability is fixed in 1.8.1.

References

Affected packages

Ubuntu:26.04:LTS / linux-entra-sso

Package

Name: linux-entra-sso
Purl: pkg:deb/ubuntu/linux-entra-sso?arch=source&distro=resolute

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Affected versions

1.*

1.7.1-1

1.7.2-1

1.8.0-1

Ecosystem specific

{
    "binaries": [
        {
            "binary_name": "linux-entra-sso",
            "binary_version": "1.8.0-1"
        }
    ]
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-42177.json"