CVE-2026-34071Public exploitNetwork attack vector

Stored XSS via unsanitized EML HTML export

Published Mar 26, 2026 · Updated Mar 26, 2026

Stored XSS in Stirling PDF 2.7.3 allows remote attackers to execute JavaScript through a malicious EML exported as HTML. ConvertEmlToPDF passes a null CustomHtmlSanitizer to the HTML-export path, so EmlProcessingUtils returns the raw email body as text/html. Execution requires an authenticated user to select Download HTML and open the result; script can reach intranet resources or present credential-harvesting forms.

CVSS severity5.4
Medium
EPSS probability0.26%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stored XSS in Stirling PDF 2.7.3 allows remote attackers to execute JavaScript through a malicious EML exported as HTML. ConvertEmlToPDF passes a null CustomHtmlSanitizer to the HTML-export path, so EmlProcessingUtils returns the raw email body as text/html. Execution requires an authenticated user to select Download HTML and open the result; script can reach intranet resources or present credential-harvesting forms.

The record

CVE
CVE-2026-34071
Published
Mar 26, 2026
Updated
Mar 26, 2026
Vendor
Stirling PDF
Product
Stirling PDF
Classifications
CWE-79, T1204.002
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 26, 2026CVE publishedPublication date reported by the CVE source.
  2. Mar 26, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion== 2.7.3

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Stirling PDF · Stirling PDFversion== 2.7.3

Published CVSS scores

6.1NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
5.4GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1204.002User Execution: Malicious File

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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