Which versions of Plantuml are affected by CVE-2026-0858?

CVE-2026-0858 presents moderate security risk, a cross-site scripting vulnerability rated CVSS 6.1. Attackers could inject scripts to steal sessions or perform actions as authenticated users.. A patch is available.

How to fix or mitigate CVE-2026-0858?

Within 30 days: Identify affected systems and apply vendor patches as part of regular patch cycle. Verify Content-Security-Policy and output encoding.

Plantuml CVE-2026-0858

Q: What is the CVSS score of CVE-2026-0858?

CVE-2026-0858 has a CVSS 4.0 base score of 2.0 (Low). CVSS vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/SC:L/SI:L/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X. EPSS exploitation probability: 0.0%.

LOW

Cross-site Scripting (XSS) (CWE-79)

2026-01-16 report@snyk.io

GHSA-hrvf-g648-rf3m

XSS Plantuml

2.0

CVSS 4.0 · NVD

Severity by source

NVD PRIMARY

2.0 LOW

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/SC:L/SI:L/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

SUSE

6.1 MEDIUM

AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Red Hat

6.1 MEDIUM

qualitative

Primary rating from NVD.

CVSS VectorNVD

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/SC:L/SI:L/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Scope

Lifecycle Timeline

Severity Changed

Apr 29, 2026 - 01:11 NVD

MEDIUM LOW

CVSS changed

Apr 29, 2026 - 01:11 NVD

6.1 (MEDIUM) 2.0 (LOW)

Analysis Generated

Mar 12, 2026 - 21:54 vuln.today

Patch released

Feb 02, 2026 - 18:52 nvd

Patch available

CVE Published

Jan 16, 2026 - 05:16 nvd

MEDIUM 6.1

Blast Radius

ecosystem impact

† from your stack dependencies † transitive graph · vuln.today resolves 4-path depth

7 maven packages depend on net.sourceforge.plantuml:plantuml (5 direct, 2 indirect)

Ecosystem-wide dependent count for version 1.2026.0.

DescriptionCVE.org

Versions of the package net.sourceforge.plantuml:plantuml before 1.2026.0 are vulnerable to Stored XSS due to insufficient sanitization of interactive attributes in GraphViz diagrams. As a result, a crafted PlantUML diagram can inject malicious JavaScript into generated SVG output, leading to arbitrary script execution in the context of applications that render the SVG.

AnalysisAI

PlantUML versions before 1.2026.0 fail to properly sanitize interactive attributes in GraphViz diagrams, allowing attackers to inject malicious JavaScript into SVG output through crafted diagram files. Applications that render these SVGs are vulnerable to arbitrary script execution within the user's browser context. A patch is available to address this stored XSS vulnerability.

Technical ContextAI

Classified as CWE-79 (Cross-site Scripting (XSS)). Affects Plantuml. Versions of the package net.sourceforge.plantuml:plantuml before 1.2026.0 are vulnerable to Stored XSS due to insufficient sanitization of interactive attributes in GraphViz diagrams. As a result, a crafted PlantUML diagram can inject malicious JavaScript into generated SVG output, leading to arbitrary script execution in the context of applications that render the SVG.

RemediationAI

A vendor patch is available — apply it immediately. Implement output encoding and Content Security Policy headers. Restrict network access to the affected service where possible.