CVE-2021-38294 | Shell Command Injection Vulnerability in Nimbus Thrift Server

Exp

A Command Injection vulnerability exists in the getTopologyHistory service of the Apache Storm 2.x prior to 2.2.1 and Apache Storm 1.x prior to 1.2.4. A specially crafted thrift request to the Nimbus server allows Remote Code Execution (RCE) prior to authentication.

Published: 2021-10-25 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-38294 is rated High Exploit Risk (86/100): CVSS Critical severity, with high exploitation likelihood (EPSS 82.06%, 99th percentile). 1 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

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

Public exploit references (Exploit-DB) for CVE-2021-38294

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2021-38294

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 2026-05-01 85.03% 82.06% -2.96%
2 2026-04-25 84.61% 85.03% +0.41%
3 2025-11-21 — 84.61% —

Full EPSS history (44 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-38294

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
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:N)
No account or special rights needed—anonymous or random user is enough.
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.
 3.9 5.9 [email protected]
7.5 2.0 HIGH
AV:N/AC:L/Au:N/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
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.
 10.0 6.4 [email protected]

Weakness enumeration for CVE-2021-38294

GitHub Security Advisory for CVE-2021-38294

GHSA-6768-mcjc-8223 · Severity: critical · Ecosystem: maven — Command injection leading to Remote Code Execution in Apache Storm

Affected software / configurations for CVE-2021-38294

Vendor Product Version Raw CPE
apache storm >= 1.0.0, < 1.2.4 cpe:2.3:a:apache:storm:*:*:*:*:*:*:*:*
apache storm >= 2.1.0, < 2.1.1 cpe:2.3:a:apache:storm:*:*:*:*:*:*:*:*
apache storm >= 2.2.0, < 2.2.1 cpe:2.3:a:apache:storm:*:*:*:*:*:*:*:*

References for CVE-2021-38294

cvelogic Threat Intelligence