Is CVE-2009-3421 being actively exploited?

CVE-2009-3421 is not currently listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

What is the CVSS score for CVE-2009-3421?

CVE-2009-3421 has a CVSS 3.1 base score of 9.8 (CRITICAL).

CVE-2009-3421

CRITICAL · CVSS 9.8EPSS 5.0%EU EUVD

login.php in Zenas PaoBacheca Guestbook 2.1, when register_globals is enabled, allows remote attackers to bypass authentication and gain administrative access by setting the login_ok parameter to 1.

Key facts

CVSS score: 9.8 (v3.1)
Severity: CRITICAL
CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness (CWE): CWE-287
EPSS score: 5.0% (92th percentile)
In CISA KEV: No
In EU EUVD: Yes (EUVD-2009-3403)
Published: September 25, 2009
NVD last modified: June 16, 2026
Status: Modified

EU Vulnerability Database (EUVD)

This vulnerability is also tracked by ENISA as EUVD-2009-3403 in the EU Vulnerability Database. Last updated in EUVD on August 7, 2024.

View on the EU Vulnerability Database

Affected products

zenas / pao-bacheca guestbook

References

http://secunia.com/advisories/36023(Broken Link, Vendor Advisory)
http://www.exploit-db.com/exploits/9293(Third Party Advisory, VDB Entry)
http://www.osvdb.org/56757(Broken Link, Exploit)
https://exchange.xforce.ibmcloud.com/vulnerabilities/52100(Third Party Advisory, VDB Entry)

Last updated September 17, 2026 · Source: NVD, CISA KEV, FIRST.org EPSS

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