How severe is CVE-2021-42857?

CVE-2021-42857 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2021-42857 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-42857?

CVE-2021-42857 primarily affects Riverbed Steelcentral Appinternals Dynamic Sampling Agent. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-42857?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-42857 published?

CVE-2021-42857 was published on 2022-03-10 and last updated on 2026-06-17.

CVE-2021-42857

CVE-2021-42857 is a medium-severity vulnerability in Riverbed Steelcentral Appinternals Dynamic Sampling Agent with a CVSS 3.x base score of 5.3. 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-22.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 5.0
EPSS exploit prediction: 1% (63rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-22
Affected product: Riverbed Steelcentral Appinternals Dynamic Sampling Agent
Published: 2022-03-10
Last modified: 2026-06-17

Description

It was discovered that the SteelCentral AppInternals Dynamic Sampling Agent's (DSA) AgentDaServlet has directory traversal vulnerabilities at the "/api/appInternals/1.0/agent/da/pcf" API. The affected endpoint does not have any validation of the user's input that allows a malicious payload to be injected.

Frequently asked questions

What is CVE-2021-42857?: It was discovered that the SteelCentral AppInternals Dynamic Sampling Agent's (DSA) AgentDaServlet has directory traversal vulnerabilities at the "/api/appInternals/1.0/agent/da/pcf" API. The affected endpoint does not have any validation of the user's input that allows a malicious payload to be injected.
How severe is CVE-2021-42857?: CVE-2021-42857 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2021-42857 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-42857?: CVE-2021-42857 primarily affects Riverbed Steelcentral Appinternals Dynamic Sampling Agent. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-42857?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-42857 published?: CVE-2021-42857 was published on 2022-03-10 and last updated on 2026-06-17.

References

https://aternity.force.com/customersuccess/s/article/Directory-Traversal-Partial-Write-at-AgentDaServlet-CVE-2021-42857

Affected products (2)

cpe:2.3:a:riverbed:steelcentral_appinternals_dynamic_sampling_agent:*:*:*:*:*:*:*:*
cpe:2.3:a:riverbed:steelcentral_appinternals_dynamic_sampling_agent:10.0.0:*:*:*:*:*:*:*

More vulnerabilities in Riverbed Steelcentral Appinternals Dynamic Sampling Agent

CVE-2021-42854 — Critical (CVSS 9.8): It was discovered that the SteelCentral AppInternals Dynamic Sampling Agent's (DSA) PluginServlet has directory…
CVE-2021-42786 — Critical (CVSS 9.8): It was discovered that the SteelCentral AppInternals Dynamic Sampling Agent (DSA) has Remote Code Execution…
CVE-2021-42787 — Critical (CVSS 9.4): It was discovered that the SteelCentral AppInternals Dynamic Sampling Agent's (DSA) AgentConfigurationServlet has…
CVE-2021-42853 — Critical (CVSS 9.1): It was discovered that the SteelCentral AppInternals Dynamic Sampling Agent's (DSA) AgentDiagnosticServlet has…
CVE-2021-42855 — High (CVSS 7.8): It was discovered that the SteelCentral AppInternals Dynamic Sampling Agent (DSA) uses the ".debug_command.config" file…
CVE-2021-42856 — Medium (CVSS 4.7): It was discovered that the /DsaDataTest endpoint is susceptible to Cross-site scripting (XSS) attack. It was noted that…

All CVEs affecting Riverbed Steelcentral Appinternals Dynamic Sampling Agent →

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