Cyber Resilience

CVE-2021-42856

Medium

Published: 10 March 2022

Published
10 March 2022
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 4.7 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:N
EPSS Score 0.0020 42.3th percentile
Risk Priority 10 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-42856 is a medium-severity Improper Input Validation (CWE-20) vulnerability in Riverbed Steelcentral Appinternals Dynamic Sampling Agent. Its CVSS base score is 4.7 (Medium).

Operationally, ranked at the 42.3th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

It was discovered that the /DsaDataTest endpoint is susceptible to Cross-site scripting (XSS) attack. It was noted that the Metric parameter does not have any input checks on the user input that allows an attacker to craft its own malicious…

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payload to trigger a XSS vulnerability.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

riverbed
steelcentral appinternals dynamic sampling agent
10.0.0 · 11.0.0 — 11.8.8 · 12.0.0 — 12.13.0

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-20 CWE-79

Directly implements checks on information inputs to reject invalid data before processing.

addresses: CWE-79

Penetration testing submits XSS payloads to web applications, detecting cross-site scripting flaws for subsequent remediation.

addresses: CWE-20

Security testing and developer training directly verify and enforce proper input validation, reducing exploitability of injection and malformed-data weaknesses.

addresses: CWE-20

Security testing and evaluation at multiple SDLC stages directly detects missing or flawed input validation, with the required remediation process ensuring fixes are applied.

addresses: CWE-79

Output validation against expected content can reject or sanitize script content in generated web pages, reducing XSS exploitability.

addresses: CWE-20

Spam protection mechanisms perform filtering and detection on inbound/outbound messages, directly compensating for missing or weak input validation of unsolicited content.

References