Reference page — cumulative record through Thursday, October 8, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.
AV AC PR UI S C I A CVSS EPSS %ile KEV N H L N C H H H 8.5 .0344 88.6 —
AFFECTED Product Versions Fixed xstream < 1.4.18 – —
TIMELINE Aug 16 Reserved by GitHub_M Aug 23 Published (CNA: GitHub_M) Oct 7 EXPLOIT PUBLISHED — CVE-2021-39150 (x-stream xstream). Public exploit reference added.
XStream is a simple library to serialize objects to XML and back again. In affected versions this vulnerability may allow a remote attacker to request data from internal resources that are not publicly available only by manipulating the processed input stream with a Java runtime version 14 to 8. No user is affected, who followed the recommendation to setup XStream's security framework with a whitelist limited to the minimal required types. If you rely on XStream's default blacklist of the [Security Framework](https://x-stream.github.io/security.html#framework), you will have to use at least version 1.4.18.
| Date | Event | Detail |
|---|---|---|
| August 16, 2021 | Reserved | Reserved by GitHub_M |
| August 23, 2021 | Published | Published (CNA: GitHub_M) |
| October 7, 2026 | EXPLOIT PUBLISHED | EXPLOIT PUBLISHED — CVE-2021-39150 (x-stream xstream). Public exploit reference added. |
| Vendor | Product / Package | Ecosystem | Version introduced | Fixed |
|---|---|---|---|---|
| x-stream | xstream | — | < 1.4.18 | — |
Authoritative record: CVE-2021-39150 at cve.org
Vendors: x-stream
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2021-39150 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Thursday, October 8, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.
