CVE-2023-4504Public exploit

Heap over-read via unterminated PostScript escape

Published Sep 21, 2023 · Updated Nov 4, 2025

Heap-based buffer over-read in OpenPrinting CUPS and libppd allows attackers to access adjacent heap memory via a malformed PPD file. The scan_ps and ppd_scan_ps routines advance past a terminal backslash without checking for the string terminator, causing a one-byte read beyond the heap allocation. Reachability requires local processing of the crafted PPD; published testing did not produce a crash, so code execution remains undemonstrated.

CVSS severity0.0
None
EPSS probability0.66%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Heap-based buffer over-read in OpenPrinting CUPS and libppd allows attackers to access adjacent heap memory via a malformed PPD file. The scan_ps and ppd_scan_ps routines advance past a terminal backslash without checking for the string terminator, causing a one-byte read beyond the heap allocation. Reachability requires local processing of the crafted PPD; published testing did not produce a crash, so code execution remains undemonstrated.

The record

CVE
CVE-2023-4504
Published
Sep 21, 2023
Updated
Nov 4, 2025
Vendor
OpenPrinting
Product
libppd
Classifications
CWE-122, T1203
Attack vector
local
Privileges
admin

Timeline

How it unfolded

  1. Sep 21, 2023CVE publishedPublication date reported by the CVE source.
  2. Nov 4, 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=0 <d09348b

What conditions does exploitation require?

Attack vectorlocal
Required privilegesadmin

What is affected?

OpenPrinting · libppdversion=0 <d09348b
OpenPrinting · CUPSversion=0 <2.4.6

Published CVSS scores

0.0GitHubCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/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.

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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)
Vectorlocal
Privilegesadmin
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-122Heap-based Buffer Overflow
T1203Exploitation for Client Execution

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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