How severe is CVE-2011-5251?

CVE-2011-5251 has a CVSS 2.0 base score of 5.8, rated medium severity.

Is CVE-2011-5251 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (72nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2011-5251?

CVE-2011-5251 primarily affects Vbulletin. In total, 13 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2011-5251?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2011-5251 published?

CVE-2011-5251 was published on 2012-12-31 and last updated on 2026-06-16.

CVE-2011-5251

CVE-2011-5251 is a medium-severity vulnerability in Vbulletin with a CVSS 2.0 base score of 5.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: Medium (CVSS 2.0 base score 5.8)
EPSS exploit prediction: 2% (72nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Vbulletin
Published: 2012-12-31
Last modified: 2026-06-16

Description

Open redirect vulnerability in forum/login.php in vBulletin 4.1.3 and earlier allows remote attackers to redirect users to arbitrary web sites and conduct phishing attacks via the url parameter in a lostpw action.

Frequently asked questions

What is CVE-2011-5251?: Open redirect vulnerability in forum/login.php in vBulletin 4.1.3 and earlier allows remote attackers to redirect users to arbitrary web sites and conduct phishing attacks via the url parameter in a lostpw action.
How severe is CVE-2011-5251?: CVE-2011-5251 has a CVSS 2.0 base score of 5.8, rated medium severity.
Is CVE-2011-5251 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (72nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2011-5251?: CVE-2011-5251 primarily affects Vbulletin. In total, 13 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2011-5251?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2011-5251 published?: CVE-2011-5251 was published on 2012-12-31 and last updated on 2026-06-16.

References

http://www.vbulletin.com/forum/showthread.php/381014-Potential-Phishing-Vector?p=2166441

Affected products (13)

cpe:2.3:a:vbulletin:vbulletin:*:*:*:*:*:*:*:*
cpe:2.3:a:vbulletin:vbulletin:4.0.0:*:*:*:*:*:*:*
cpe:2.3:a:vbulletin:vbulletin:4.0.1:*:*:*:*:*:*:*
cpe:2.3:a:vbulletin:vbulletin:4.0.2:*:*:*:*:*:*:*
cpe:2.3:a:vbulletin:vbulletin:4.0.3:*:*:*:*:*:*:*
cpe:2.3:a:vbulletin:vbulletin:4.0.4:*:*:*:*:*:*:*
cpe:2.3:a:vbulletin:vbulletin:4.0.5:*:*:*:*:*:*:*
cpe:2.3:a:vbulletin:vbulletin:4.0.6:*:*:*:*:*:*:*
cpe:2.3:a:vbulletin:vbulletin:4.0.7:*:*:*:*:*:*:*
cpe:2.3:a:vbulletin:vbulletin:4.0.8:*:*:*:*:*:*:*
cpe:2.3:a:vbulletin:vbulletin:4.1:*:*:*:*:*:*:*
cpe:2.3:a:vbulletin:vbulletin:4.1.1:*:*:*:*:*:*:*
cpe:2.3:a:vbulletin:vbulletin:4.1.2:*:*:*:*:*:*:*

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