CVE-2021-42855 | Local privilege escalation due to misconfigured write permission on .debug_command.config file

It was discovered that the SteelCentral AppInternals Dynamic Sampling Agent (DSA) uses the ".debug_command.config" file to store a json string that contains a list of IDs and pre-configured commands. The config file is subsequently used by the "/api/appInternals/1.0/agent/configuration" API to map the corresponding ID to a command to be executed.

Published: 2022-03-10 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-42855 is rated Low Risk (34.3/100): CVSS High severity, with low exploitation likelihood (EPSS 0.04%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2021-42855

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2025-03-30 0.08% 0.04% -0.04%
2 2025-03-29 0.04% 0.08% +0.03%
3 2023-03-07 — 0.04% —

Full EPSS history (4 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-42855

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.8 3.1 HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.8 5.9 [email protected]
7.8 3.1 HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.8 5.9 [email protected]
4.6 2.0 MEDIUM
AV:L/AC:L/Au:N/C:P/I:P/A:P Click to expand
Access vector (AV:L)
Requires local access to the target system.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 3.9 6.4 [email protected]

Weakness enumeration for CVE-2021-42855

Affected software / configurations for CVE-2021-42855

Vendor Product Version Raw CPE
riverbed steelcentral_appinternals_dynamic_sampling_agent >= 11.0.0, < 11.8.8 cpe:2.3:a:riverbed:steelcentral_appinternals_dynamic_sampling_agent:*:*:*:*:*:*:*:*
riverbed steelcentral_appinternals_dynamic_sampling_agent >= 12.0.0, < 12.13.0 cpe:2.3:a:riverbed:steelcentral_appinternals_dynamic_sampling_agent:*:*:*:*:*:*:*:*
riverbed steelcentral_appinternals_dynamic_sampling_agent 10.0.0 cpe:2.3:a:riverbed:steelcentral_appinternals_dynamic_sampling_agent:10.0.0:*:*:*:*:*:*:*

References for CVE-2021-42855

cvelogic Threat Intelligence