How severe is CVE-2011-4755?

CVE-2011-4755 has a CVSS 2.0 base score of 10.0, rated critical severity.

Is CVE-2011-4755 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2011-4755?

CVE-2011-4755 affects Parallels Parallels Plesk Small Business Panel. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2011-4755?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2011-4755 published?

CVE-2011-4755 was published on 2011-12-16 and last updated on 2026-06-16.

CVE-2011-4755

CVE-2011-4755 is a critical-severity vulnerability in Parallels Parallels Plesk Small Business Panel with a CVSS 2.0 base score of 10.0. 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: Critical (CVSS 2.0 base score 10.0)
EPSS exploit prediction: 2% (78th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Parallels Parallels Plesk Small Business Panel
Published: 2011-12-16
Last modified: 2026-06-16

Description

Parallels Plesk Small Business Panel 10.2.0 does not properly validate string data that is intended for storage in an XML document, which allows remote attackers to cause a denial of service (parsing error) or possibly have unspecified other impact via a crafted cookie, as demonstrated by cookies to client@1/domain@1/hosting/file-manager/ and certain other files.

Frequently asked questions

What is CVE-2011-4755?: Parallels Plesk Small Business Panel 10.2.0 does not properly validate string data that is intended for storage in an XML document, which allows remote attackers to cause a denial of service (parsing error) or possibly have unspecified other impact via a crafted cookie, as demonstrated by cookies to client@1/domain@1/hosting/file-manager/ and certain other files.
How severe is CVE-2011-4755?: CVE-2011-4755 has a CVSS 2.0 base score of 10.0, rated critical severity.
Is CVE-2011-4755 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2011-4755?: CVE-2011-4755 affects Parallels Parallels Plesk Small Business Panel. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2011-4755?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2011-4755 published?: CVE-2011-4755 was published on 2011-12-16 and last updated on 2026-06-16.

References

Affected products (1)

cpe:2.3:a:parallels:parallels_plesk_small_business_panel:10.2.0:*:*:*:*:*:*:*

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