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CVE-2021-21349

A Server-Side Forgery Request can be activated unmarshalling with XStream to access data streams from an arbitrary URL referencing a resource in an intranet or the local host

HIGH
8.6
CVSS Score
Published: March 22, 2021 at 11:45 PM UTC
Updated: October 7, 2026 at 07:17 PM UTC
17 products affected across 6 vendorsDebian LinuxFedoraOnCommand Insight

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Severity
HIGH8.6
Exploit prediction
EPSS 47%
SSVC
No known exploit

Description

XStream is a Java library to serialize objects to XML and back again. In XStream before version 1.4.16, there is a vulnerability which may allow a remote attacker to request data from internal resources that are not publicly available 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. If you rely on XStream's default blacklist of the Security Framework, you will have to use at least version 1.4.16.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

References (15)

x_refsource_MISCRelease NotesThird Party Advisory
Source: [email protected]
http://x-stream.github.io/changes.html#1.4.16
x_refsource_CONFIRMThird Party Advisory
Source: [email protected]
https://github.com/x-stream/xstream/security/advisories/GHSA-f6hm-88x3-mfjv
Mailing Listx_refsource_MLISTIssue TrackingThird Party Advisory
Source: [email protected]
https://lists.apache.org/thread.html/r8244fd0831db894d5e89911ded9c72196d395a90ae655414d23ed0dd%40%3Cusers.activemq.apache.org%3E
Mailing Listx_refsource_MLISTIssue TrackingThird Party Advisory
Source: [email protected]
https://lists.apache.org/thread.html/r9ac71b047767205aa22e3a08cb33f3e0586de6b2fac48b425c6e16b0%40%3Cdev.jmeter.apache.org%3E
Mailing Listx_refsource_MLISTThird Party Advisory
Source: [email protected]
https://lists.debian.org/debian-lts-announce/2021/04/msg00002.html
Vendor Advisoryx_refsource_FEDORAMailing ListThird Party Advisory
Source: [email protected]
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/22KVR6B5IZP3BGQ3HPWIO2FWWCKT3DHP/
Vendor Advisoryx_refsource_FEDORAMailing ListThird Party Advisory
Source: [email protected]
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PVPHZA7VW2RRSDCOIPP2W6O5ND254TU7/
Vendor Advisoryx_refsource_FEDORAMailing ListThird Party Advisory
Source: [email protected]
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QGXIU3YDPG6OGTDHMBLAFN7BPBERXREB/

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

8.6HIGH[email protected]
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
CHANGED
Confidentiality
HIGH
Integrity
NONE
Availability
NONE
Vector?

Quick Info

StatusANALYZED
CWE
CWE-502CWE-918

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