Answer in brief
CVE-2021-29505 records a High severity (CVSS 7.5) vulnerability in XStream is vulnerable to a Remote Command Execution attack. The current sources do not mark it as known exploited. The current feed maps x-stream/xstream (generic), com.thoughtworks.xstream:xstream (maven). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 7.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps x-stream/xstream (generic), com.thoughtworks.xstream:xstream (maven). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| x-stream/xstreamgeneric | <1.4.17 | 1.4.17 |
| com.thoughtworks.xstream:xstreammaven | >=0 <1.4.17 | 1.4.17 |
Published upstream
May 28, 2021
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 7, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 8, 2026
XStream is software for serializing Java objects to XML and back again. A vulnerability in XStream versions prior to 1.4.17 may allow a remote attacker has sufficient rights to execute commands of the host only by manipulating the processed input stream. No user who followed the recommendation to setup XStream's security framework with a whitelist limited to the minimal required types is affected. The vulnerability is patched in version 1.4.17.
Quoted source text, attributed separately from HOL analysis.