How severe is CVE-2021-35252?

CVE-2021-35252 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2021-35252 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-35252?

CVE-2021-35252 affects Solarwinds Serv-u. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-35252?

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-2021-35252 published?

CVE-2021-35252 was published on 2022-12-16 and last updated on 2026-06-17.

CVE-2021-35252

CVE-2021-35252 is a high-severity vulnerability in Solarwinds Serv-u with a CVSS 3.x base score of 7.5. 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-287.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (41st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Solarwinds Serv-u
Published: 2022-12-16
Last modified: 2026-06-17

Description

Common encryption key appears to be used across all deployed instances of Serv-U FTP Server. Because of this an encrypted value that is exposed to an attacker can be simply recovered to plaintext.

Frequently asked questions

What is CVE-2021-35252?: Common encryption key appears to be used across all deployed instances of Serv-U FTP Server. Because of this an encrypted value that is exposed to an attacker can be simply recovered to plaintext.
How severe is CVE-2021-35252?: CVE-2021-35252 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-35252 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-35252?: CVE-2021-35252 affects Solarwinds Serv-u. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-35252?: 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-2021-35252 published?: CVE-2021-35252 was published on 2022-12-16 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:solarwinds:serv-u:*:*:*:*:*:*:*:*

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Other CWE-287 (Improper Authentication) vulnerabilities

CVE-2026-45480 — Critical (CVSS 10.0): Improper authentication in Azure Active Directory allows an unauthorized attacker to elevate privileges over a network.
CVE-2026-46389 — Critical (CVSS 10.0): UDS Identity Config builds the Keycloak configuration image (realm, plugins, theme, truststore, JARs) consumed by UDS…
CVE-2026-10611 — Critical (CVSS 10.0): An authentication bypass vulnerability exists in MISP when LDAP mixed authentication is enabled with OTP enforcement.…
CVE-2026-47280 — Critical (CVSS 10.0): Improper authentication in Azure Resource Manager (ARM) allows an unauthorized attacker to elevate privileges over a…
CVE-2026-42822 — Critical (CVSS 10.0): Improper authentication in Azure Local Disconnected Operations allows an unauthorized attacker to elevate privileges…
CVE-2026-20182 — Critical (CVSS 10.0): May 2026: This security advisory provides the details and fix information for a vulnerability that was discovered and…

Browse all CWE-287 (Improper Authentication) vulnerabilities →