How severe is CVE-2021-34992?

CVE-2021-34992 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-34992 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (90th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-34992?

CVE-2021-34992 affects Orckestra C1 Cms. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-34992?

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

When was CVE-2021-34992 published?

CVE-2021-34992 was published on 2021-11-15 and last updated on 2026-06-17.

CVE-2021-34992

CVE-2021-34992 is a high-severity vulnerability in Orckestra C1 Cms with a CVSS 3.x base score of 8.8. 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-502.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 6.5
EPSS exploit prediction: 4% (90th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-502
Affected product: Orckestra C1 Cms
Published: 2021-11-15
Last modified: 2026-06-17

Description

This vulnerability allows remote attackers to execute arbitrary code on affected installations of Orckestra C1 CMS 6.10. Authentication is required to exploit this vulnerability. The specific flaw exists within Composite.dll. The issue results from the lack of proper validation of user-supplied data, which can result in deserialization of untrusted data. An attacker can leverage this vulnerability to execute code in the context of the service account. Was ZDI-CAN-14740.

Frequently asked questions

What is CVE-2021-34992?: This vulnerability allows remote attackers to execute arbitrary code on affected installations of Orckestra C1 CMS 6.10. Authentication is required to exploit this vulnerability. The specific flaw exists within Composite.dll. The issue results from the lack of proper validation of user-supplied data, which can result in deserialization of untrusted data. An attacker can leverage this vulnerability to execute code in the context of the service account. Was ZDI-CAN-14740.
How severe is CVE-2021-34992?: CVE-2021-34992 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-34992 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (90th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-34992?: CVE-2021-34992 affects Orckestra C1 Cms. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-34992?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-34992 published?: CVE-2021-34992 was published on 2021-11-15 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:orckestra:c1_cms:6.10:*:*:*:*:*:*:*

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