CVE-2025-55151Public exploitNetwork attack vector

Unauthenticated SSRF via unoconvert HTML resource fetching

Published Aug 11, 2025 · Updated Aug 12, 2025

SSRF in Stirling PDF before 1.1.0 allows remote attackers to make server-side requests through uploaded HTML file conversion. The /api/v1/convert/file/pdf handler passes uploaded HTML to LibreOffice's unoconvert, which fetches attacker-selected image URLs without restricting localhost, private, link-local, or metadata destinations. No authentication or user interaction is required, and resulting requests can reach resources available to the application host.

CVSS severity8.6
High
EPSS probability0.36%
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 make server-side requests through uploaded HTML file conversion. The /api/v1/convert/file/pdf handler passes uploaded HTML to LibreOffice's unoconvert, which fetches attacker-selected image URLs without restricting localhost, private, link-local, or metadata destinations. No authentication or user interaction is required, and resulting requests can reach resources available to the application host.

The record

CVE
CVE-2025-55151
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

8.6GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:L
9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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 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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