CVE-2020-23878Public exploitNetwork attack vector

Converter crash via recursive PDF object streams

Published Nov 10, 2021 · Updated Aug 4, 2024

Stack overflow in pdf2json 0.71 allows attackers to crash the converter by supplying a crafted PDF with recursive object streams. XRef::fetch constructs an ObjectStream that calls XRef::fetch again for a cyclic reference, recursing until the process stack is exhausted. Exposure depends on a surrounding application passing attacker-supplied PDF files to the converter; the demonstrated consequence is a process crash.

CVSS severity9.8
Critical
EPSS probability1.76%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stack overflow in pdf2json 0.71 allows attackers to crash the converter by supplying a crafted PDF with recursive object streams. XRef::fetch constructs an ObjectStream that calls XRef::fetch again for a cyclic reference, recursing until the process stack is exhausted. Exposure depends on a surrounding application passing attacker-supplied PDF files to the converter; the demonstrated consequence is a process crash.

The record

CVE
CVE-2020-23878
Published
Nov 10, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-787, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Nov 10, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 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

7.5NIST NVDAV:N/AC:L/Au:N/C:P/I:P/A:P
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.

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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-787Out-of-bounds Write
T1499.004Application or System Exploitation

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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