CVE-2025-55161Public exploitNetwork attack vector

Internal resource access via bypassed image URL sanitization

Published Aug 11, 2025 · Updated Aug 12, 2025

SSRF in Stirling-PDF before 1.1.0 allows remote attackers to access internal resources through crafted Markdown image URLs. ConvertMarkdownToPdf passes attacker-controlled image sources through org.owasp.html sanitization to FileToPdf, which fetches URLs without blocking private, localhost, link-local, or metadata addresses. The unauthenticated network endpoint requires no user interaction; successful requests expose sensitive internal data and alter or interrupt reachable services.

CVSS severity8.6
High
EPSS probability2.00%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

SSRF in Stirling-PDF before 1.1.0 allows remote attackers to access internal resources through crafted Markdown image URLs. ConvertMarkdownToPdf passes attacker-controlled image sources through org.owasp.html sanitization to FileToPdf, which fetches URLs without blocking private, localhost, link-local, or metadata addresses. The unauthenticated network endpoint requires no user interaction; successful requests expose sensitive internal data and alter or interrupt reachable services.

The record

CVE
CVE-2025-55161
Published
Aug 11, 2025
Updated
Aug 12, 2025
Vendor
Stirling PDF
Product
Stirling PDF
Classifications
CWE-918, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 11, 2025CVE publishedPublication date reported by the CVE source.
  2. Aug 12, 2025Record 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=< 1.1.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Stirling PDF · Stirling PDFversion=< 1.1.0

Published CVSS scores

8.6GitHubCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:L

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.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-918Server-Side Request Forgery (SSRF)
T1190Exploit Public-Facing Application

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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