CVE-2021-39144: XStream Remote Code Execution Vulnerability

Vulnerability summary

CVE-2021-39144 is a high (CVSS 8.5) Code Injection vulnerability in XStream. It is known to be exploited: CISA lists it, first on 10-03-2023. EPSS estimates a 98.12% chance of exploitation in the next 30 days, higher than 99.9% of scored vulnerabilities. 3 public exploits are recorded.

Timeline

1. 23-08-2021
   PublishedVulnerability first disclosed.
2. 10-03-2023
   Added to CISA KEVXStream Remote Code Execution Vulnerability
3. 31-03-2023
   CISA remediation dueApply updates per vendor instructions.
4. 21-10-2025
   Last modifiedVulnerability information updated.

Description

XStream is a simple library to serialize objects to XML and back again. In affected versions this vulnerability may allow a remote attacker has sufficient rights to execute commands of the host only by manipulating the processed input stream. No user is affected, who followed the recommendation to setup XStream's security framework with a whitelist limited to the minimal required types. XStream 1.4.18 uses no longer a blacklist by default, since it cannot be secured for general purpose.

• CWE-94Improper Control of Generation of Code ('Code Injection')The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment.
• CWE-502Deserialization of Untrusted DataThe product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.
• CWE-306Missing Authentication for Critical FunctionThe product does not perform any authentication for functionality that requires a provable user identity or consumes a significant amount of resources.