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Back to active CVEs
Medium · CVSS 6.8CVE-2020-26259GHSA-JFVX-7WRX-43FH

XStream is vulnerable to an Arbitrary File Deletion on the local host when unmarshallingCVE-2020-26259

Answer in brief

CVE-2020-26259 records a Medium severity (CVSS 6.8) vulnerability in XStream is vulnerable to an Arbitrary File Deletion on the local host when unmarshalling. 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.

Published Dec 16, 2020Updated Oct 7, 2026Source checked Oct 7, 2026First seen by HOL Aug 8, 2026Material review Oct 7, 2026
Upstream Advisory

Key facts

Risk
Medium · CVSS 6.8
Exploitation
Not marked as known exploited
Affected software
2 mapped packages or products
Fix availability
Available

Why this deserves its current priority

CVSS is 6.8. 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.

Affected scope and exposure questions

The current feed maps x-stream/xstream (generic), com.thoughtworks.xstream:xstream (maven). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
PackageAffected rangeFixed version
x-stream/xstreamgeneric<1.4.151.4.15
com.thoughtworks.xstream:xstreammaven>=0 <1.4.151.4.15

Recommended response

  1. 1Check inventory. Check lockfiles and deployed manifests for x-stream/xstream, com.thoughtworks.xstream:xstream.
  2. 2Review the reported fix. Update x-stream/xstream to 1.4.15; com.thoughtworks.xstream:xstream to 1.4.15 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

  1. Published upstream

    Dec 16, 2020

    Evidence: source:cvelist:source_dates:source-dates:record
  2. Source modified

    Oct 7, 2026

    Evidence: source:cvelist:source_dates:source-dates:record
  3. First seen by HOL

    Aug 8, 2026

Sources and claim methodology

  • GitHub security advisorygithub.com
  • Source referencelists.apache.org
  • Source referencelists.debian.org
  • Source referencelists.fedoraproject.org
  • Source referencelists.fedoraproject.org
  • Source referencelists.fedoraproject.org
  • Source referencesecurity.netapp.com
  • Source referencedebian.org
  • Source referencex-stream.github.io
  • GitHub security advisorygithub.com
  • Source referencelists.apache.org
  • Source referencelists.fedoraproject.org
  • Source referencelists.fedoraproject.org
  • Source referencelists.fedoraproject.org
  • NVD vulnerability recordnvd.nist.gov
  • Source referencesecurity.netapp.com
Upstream source description

XStream is a Java library to serialize objects to XML and back again. In XStream before version 1.4.15, is vulnerable to an Arbitrary File Deletion on the local host when unmarshalling. The vulnerability may allow a remote attacker to delete arbitrary know files on the host as log as the executing process has sufficient rights only by manipulating the processed input stream. If you rely on XStream's default blacklist of the Security Framework, you will have to use at least version 1.4.15. The reported vulnerability does not exist running Java 15 or higher. No user is affected, who followed the recommendation to setup XStream's Security Framework with a whitelist! Anyone relying on XStream's default blacklist can immediately switch to a whilelist for the allowed types to avoid the vulnerability. Users of XStream 1.4.14 or below who still want to use XStream default blacklist can use a workaround described in more detailed in the referenced advisories.

Quoted source text, attributed separately from HOL analysis.

Related CVEs

  • Apache Geode: Management REST API: Insertion of Sensitive Information into Log FileSame generic ecosystem
  • Gimp: gimp: heap buffer overflow in pcx export on oversized image dimensionsSame generic ecosystem
  • Gimp: gimp: heap buffer overflow in raw data export on oversized image dimensionsSame generic ecosystem
  • Gimp: gimp: heap buffer overflow in hot color filter on oversized imageSame generic ecosystem
  • Infinite Loop in Telerik Document Processing XLS ImportSame generic ecosystem
  • Backstage: Improper input validation in TechDocs Markdown extension configurationSame generic ecosystem

Record context

Vulnerability class
Command Injection
EPSS
Not reported
CWE IDs
CWE-78
Source
CVE List V5
Source checked
Oct 7, 2026
References
16 linked sources
Open source record