CVE-2018-21237Network attack vector

NTLM credential theft via remote PDF actions

Published Jun 4, 2020 · Updated Aug 5, 2024

Credential disclosure in Foxit PhantomPDF before 8.3.7 allows remote attackers to obtain NTLM credentials through a crafted PDF. The GoToE and GoToR action handlers follow attacker-controlled remote file references and cause Windows to send NTLM authentication material. Reachability requires PhantomPDF to process the crafted action; no code execution, data modification, or service interruption is reported.

CVSS severity5.3
Medium
EPSS probability0.82%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Credential disclosure in Foxit PhantomPDF before 8.3.7 allows remote attackers to obtain NTLM credentials through a crafted PDF. The GoToE and GoToR action handlers follow attacker-controlled remote file references and cause Windows to send NTLM authentication material. Reachability requires PhantomPDF to process the crafted action; no code execution, data modification, or service interruption is reported.

The record

CVE
CVE-2018-21237
Published
Jun 4, 2020
Updated
Aug 5, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-522, T1187
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 4, 2020CVE publishedPublication date reported by the CVE source.
  2. Aug 5, 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?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

5.3NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
5.0NIST NVDAV:N/AC:L/Au:N/C:P/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 exploitUnconfirmed

Weakness, pattern, technique

CWE-522Insufficiently Protected Credentials
T1187Forced Authentication

Public exploit references

No public exploit references are available in this record.

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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