CVE-2020-26217

Remote Code Execution in XStream

HIGH 8.8EPSS 85.0%

XStream before version 1.4.14 is vulnerable to Remote Code Execution.The vulnerability may allow a remote attacker to run arbitrary shell commands only by manipulating the processed input stream. Only users who rely on blocklists are affected. Anyone using XStream's Security Framework allowlist is not affected. The linked advisory provides code workarounds for users who cannot upgrade. The issue is fixed in version 1.4.14.

Affected: x-stream · xstream
CVSS v3.1 NVD: 8.8 HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CVSS v3.1 GITHUB: 8.0 HIGHCVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:H
CVSS v2.0 NVD: 9.3 HIGHAV:N/AC:M/Au:N/C:C/I:C/A:C
EPSS: 85.00% chance of exploitation in the next 30 days, 100th percentile
Nuclei: high · CWE-78
Published: 2020-11-16
Updated: 2026-10-07

Proof-of-concept exploits (8)

Al1ex/CVE-2020-262173★ · 2021-01-22
Veraxy00/XStream-vul-poc4★ · 2020-12-15
cuijiung/xstream-CVE-2020-262170★ · 2025-07-17
hex0wn/learn-java-bug74★ · 2022-06-21
jas502n/CVE-2020-2625925★ · 2020-12-13
novysodope/CVE-2020-26217-XStream-RCE-POC4★ · 2020-12-08
shoucheng3/x-stream__xstream_CVE-2020-26217_1-4-14-java70★ · 2025-08-23
Kairo-one/CVE-2020-26217-XStream2★ · 2025-12-01

Nuclei templates (1)

projectdiscovery/nuclei-templates/blob/main/http/cves/2020/CVE-2020-26217.yaml

CVE-2020-26217

Proof-of-concept exploits (8)

Nuclei templates (1)

Security advisories

References

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