CVE-2025-47241: Browser Use allows bypassing `allowed_domains` by putting a decoy domain in http auth username portion of a URL

Should you act?

Normal patch cycle

No exploitation signal; fix it in your next routine update if you are affected. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.

• Not in CISA KEV, but CISA’s SSVC assessment records a public proof-of-concept, so attack code exists.
• EPSS 0.5%, percentile 38: FIRST’s model estimates a 0.5% chance of exploitation activity in the next 30 days, higher than 38% of all scored CVEs (low). EPSS is a probability, not a verdict.
• Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
• Only applies if your dependency tree includes browser-use (PyPI) <= 0.1.44, fixed in 0.1.45. Check your lockfile, including transitive dependencies.

What it is

In browser-use (aka Browser Use) before 0.1.45, URL parsing of alloweddomains is mishandled because userinfo can be placed in the authority component.

From the GitHub advisory

Summary During a manual source code review, ARIMLABS.AI researchers identified that the browseruse module includes an embedded whitelist functionality to restrict URLs that can be visited. This restriction is enforced during agent initialization. However, it was discovered that these measures can be bypassed, leading to severe security implications.

Details File: browseruse/browser/context.py

The BrowserContextConfig class defines an alloweddomains list, which is intended to limit accessible domains. This list is checked in the isurlallowed() method before navigation:

The isurlallowed() method is responsible for checking whether a given URL is permitted:

The core issue stems from the line domain = domain.split(':')[0], which allows an attacker to manipulate basic authentication credentials by providing a username:password pair. By replacing the username with a whitelisted domain, the check can be bypassed, even though the actual domain remains different. Proof of Concept (PoC)

Weakness type: CWE-647.

Product: browser-use (PyPI) · Assigned by: mitre · Published: 2025-05-03

Affected and fixed versions

Severity scores

• Attack vector: network (remotely reachable)
• Attack complexity: high (needs special conditions)
• Privileges required: none (no login)
• User interaction: none
• Scope: changed (can affect other components)

CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.

Exploitation and urgency

• CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
• CISA SSVC assessment: exploitation poc, automatable no, technical impact partial.
• FIRST EPSS (model of 2026-10-21): 0.45% probability of exploitation activity in the next 30 days; percentile 38.

Timeline

• 2025-05-03 — CVE record published by mitre
• 2025-05-05 — CVE record last updated
• 2025-05-05 — GitHub-reviewed advisory GHSA-x39x-9qw5-ghrf published (critical)

Sources and references

Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.

Vulnerability records

1. GitHub Advisory GHSA-x39x-9qw5-ghrf github.com
2. CVE.org record CVE-2025-47241 cve.org
3. NVD entry CVE-2025-47241 nvd.nist.gov

Other references from the CVE record and advisory

1. github.com github.com
2. github.com github.com
3. github.com github.com

Critical PyPI advisories · Today’s Security Digest