Is CVE-2021-35247 in the CISA KEV catalog?

Yes. CVE-2021-35247 is on the CISA Known Exploited Vulnerabilities list, added 2022-01-21.

What is the CVSS severity of CVE-2021-35247?

CVE-2021-35247 has a CVSS v3 base score of 4.3 (MEDIUM).

What is the EPSS score for CVE-2021-35247?

CVE-2021-35247 has an EPSS score of 3.36% (87th percentile), estimating the probability of exploitation in the next 30 days.

CVE & CISA-KEV Catalog

CVE-2021-35247

MEDIUMCISA KEVEPSS 87th pctl

4.3

CVSS v3

NVD

Description

Serv-U web login screen to LDAP authentication was allowing characters that were not sufficiently sanitized. SolarWinds has updated the input mechanism to perform additional validation and sanitization. Please Note: No downstream affect has been detected as the LDAP servers ignored improper characters. To insure proper input validation is completed in all environments. SolarWinds recommends scheduling an update to the latest version of Serv-U.

CWE-20Improper Input Validation

CVSS v3 Vector

Exploitability

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredNone

User InteractionRequired

ScopeUnchanged

Impact

ConfidentialityNone

IntegrityLow

AvailabilityNone

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N

Exploit Intelligence

3.36%probability of exploitation in 30 days

87thpercentile

Elevated risk: more likely to be exploited than 87% of all known CVEs.

Known Exploited Vulnerability (CISA KEV)

SolarWinds Serv-U Improper Input Validation Vulnerability

SolarWinds Serv-U versions 15.2.5 and earlier contain an improper input validation vulnerability that allows attackers to build and send queries without sanitization.

Apply updates per vendor instructions.

Remediation due: 2022-02-04

References

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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2025-10-27.