CVE-2021-23345Public exploitNetwork attack vector

Unauthenticated local file disclosure via unfiltered iframe source

Published Feb 26, 2021 · Updated Sep 16, 2024

SSRF in Gotenberg before 7.0.0 allows remote attackers to read server-local files through crafted HTML conversion requests. The /convert/html handler renders attacker-supplied HTML in Chromium without blocking file:// subresources, so an iframe can embed a local file in the returned PDF. API reachability is sufficient; the demonstrated consequence is disclosure of files readable by the container, with no reported write or execution.

CVSS severity5.3
Medium
EPSS probability1.05%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

SSRF in Gotenberg before 7.0.0 allows remote attackers to read server-local files through crafted HTML conversion requests. The /convert/html handler renders attacker-supplied HTML in Chromium without blocking file:// subresources, so an iframe can embed a local file in the returned PDF. API reachability is sufficient; the demonstrated consequence is disclosure of files readable by the container, with no reported write or execution.

The record

CVE
CVE-2021-23345
Published
Feb 26, 2021
Updated
Sep 16, 2024
Vendor
Gotenberg
Product
Gotenberg
Classifications
CWE-918, T1190, T1005
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 26, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 2024Record 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=0 <unspecified

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Gotenberg · Gotenbergversion=0 <unspecified

Published CVSS scores

5.0NVDAV:N/AC:L/Au:N/C:P/I:N/A:N
5.3SnykCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/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-918Server-Side Request Forgery (SSRF)
T1190Exploit Public-Facing Application
T1005Data from Local System

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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