CVE-2020-18839Public exploitNetwork attack vector

Application crash via uninitialized page pointer

Published Aug 22, 2023 · Updated Oct 4, 2024

Buffer overflow in HtmlOutputDev::page in Poppler 0.75.0 allows attackers to crash pdftohtml by processing a crafted PDF file. The HtmlOutputDev destructor passes an uninitialized page FILE pointer to fputs when object construction leaves that member unset. Opening or otherwise processing the crafted document with pdftohtml triggers undefined behavior and terminates that conversion process.

CVSS severity6.5
Medium
EPSS probability0.65%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Buffer overflow in HtmlOutputDev::page in Poppler 0.75.0 allows attackers to crash pdftohtml by processing a crafted PDF file. The HtmlOutputDev destructor passes an uninitialized page FILE pointer to fputs when object construction leaves that member unset. Opening or otherwise processing the crafted document with pdftohtml triggers undefined behavior and terminates that conversion process.

The record

CVE
CVE-2020-18839
Published
Aug 22, 2023
Updated
Oct 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-787, T1204.002
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 22, 2023CVE publishedPublication date reported by the CVE source.
  2. Oct 4, 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

6.5NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/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.

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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-787Out-of-bounds Write
T1204.002Malicious 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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