CVE-2021-32647
CVE-2021-32647 is a high-severity vulnerability in Nsa Emissary with a CVSS 3.x base score of 8.0. 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-470.
Key facts
- Severity: High (CVSS 3.x base score 8.0)
- CVSS v2: 6.5
- EPSS exploit prediction: 3% (85th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-470
- Affected product: Nsa Emissary
- Published:
- Last modified:
Description
Emissary is a P2P based data-driven workflow engine. Affected versions of Emissary are vulnerable to post-authentication Remote Code Execution (RCE). The [`CreatePlace`](https://github.com/NationalSecurityAgency/emissary/blob/30c54ef16c6eb6ed09604a929939fb9f66868382/src/main/java/emissary/server/mvc/internal/CreatePlaceAction.java#L36) REST endpoint accepts an `sppClassName` parameter which is used to load an arbitrary class. This class is later instantiated using a constructor with the following signature: `<constructor>(String, String, String)`. An attacker may find a gadget (class) in the application classpath that could be used to achieve Remote Code Execution (RCE) or disrupt the application. Even though the chances to find a gadget (class) that allow arbitrary code execution are low, an attacker can still find gadgets that could potentially crash the application or leak sensitive data. As a work around disable network access to Emissary from untrusted sources.
Frequently asked questions
- What is CVE-2021-32647?
- Emissary is a P2P based data-driven workflow engine. Affected versions of Emissary are vulnerable to post-authentication Remote Code Execution (RCE). The [`CreatePlace`](https://github.com/NationalSecurityAgency/emissary/blob/30c54ef16c6eb6ed09604a929939fb9f66868382/src/main/java/emissary/server/mvc/internal/CreatePlaceAction.java#L36) REST endpoint accepts an `sppClassName` parameter which is used to load an arbitrary class. This class is later instantiated using a constructor with the following signature: `<constructor>(String, String, String)`. An attacker may find a gadget (class) in the application classpath that could be used to achieve Remote Code Execution (RCE) or disrupt the application. Even though the chances to find a gadget (class) that allow arbitrary code execution are low, an attacker can still find gadgets that could potentially crash the application or leak sensitive data. As a work around disable network access to Emissary from untrusted sources.
- How severe is CVE-2021-32647?
- CVE-2021-32647 has a CVSS 3.x base score of 8.0, rated high severity. It is exploitable over network with high attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2021-32647 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (85th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-32647?
- CVE-2021-32647 affects Nsa Emissary. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-32647?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2021-32647 published?
- CVE-2021-32647 was published on 2021-06-01 and last updated on 2026-06-17.
References
- https://github.com/NationalSecurityAgency/emissary/blob/30c54ef16c6eb6ed09604a929939fb9f66868382/src/main/java/emissary/server/mvc/internal/CreatePlaceAction.java#L36
- https://github.com/NationalSecurityAgency/emissary/security/advisories/GHSA-ph73-7v9r-wg32
Affected products (1)
- cpe:2.3:a:nsa:emissary:6.4.0:*:*:*:*:*:*:*
More vulnerabilities in Nsa Emissary
- CVE-2026-35580 — Critical (CVSS 9.1): Emissary is a P2P based data-driven workflow engine. Prior to 8.39.0, GitHub Actions workflow files contained shell…
- CVE-2026-35582 — High (CVSS 8.8): Emissary is a P2P based data-driven workflow engine. In versions 8.42.0 and below, Executrix.getCommand() is vulnerable…
- CVE-2021-32096 — High (CVSS 8.8): The ConsoleAction component of U.S. National Security Agency (NSA) Emissary 5.9.0 allows a CSRF attack that results in…
- CVE-2021-32094 — High (CVSS 8.8): U.S. National Security Agency (NSA) Emissary 5.9.0 allows an authenticated user to upload arbitrary files.
- CVE-2021-32095 — High (CVSS 8.1): U.S. National Security Agency (NSA) Emissary 5.9.0 allows an authenticated user to delete arbitrary files.
- CVE-2026-35581 — High (CVSS 7.2): Emissary is a P2P based data-driven workflow engine. Prior to 8.39.0, the Executrix utility class constructed shell…
All CVEs affecting Nsa Emissary →
Other CWE-470 (Unsafe Reflection) vulnerabilities
- CVE-2026-42027 — Critical (CVSS 9.8): Arbitrary Class Instantiation via Model Manifest in Apache OpenNLP ExtensionLoader Versions Affected: before…
- CVE-2025-34393 — Critical (CVSS 9.8): Barracuda Service Center, as implemented in the RMM solution, in versions prior to 2025.1.1, does not correctly verify…
- CVE-2025-53693 — Critical (CVSS 9.8): Use of Externally-Controlled Input to Select Classes or Code ('Unsafe Reflection') vulnerability in Sitecore Sitecore…
- CVE-2023-6943 — Critical (CVSS 9.8): Use of Externally-Controlled Input to Select Classes or Code ('Unsafe Reflection') vulnerability in Mitsubishi Electric…
- CVE-2021-31522 — Critical (CVSS 9.8): Kylin can receive user input and load any class through Class.forName(...). This issue affects Apache Kylin 2 version…
- CVE-2019-1003041 — Critical (CVSS 9.8): A sandbox bypass vulnerability in Jenkins Pipeline: Groovy Plugin 2.64 and earlier allows attackers to invoke arbitrary…