CVE-2026-55453Public exploitHinoki check available

Queue disruption via printer-status newline injection

Published Oct 15, 2026 · Updated Oct 15, 2026

Status-line injection in OpenPrinting CUPS before 2.4.20 allows attackers to disrupt a print queue through a malicious IPP printer. In backend/ipp.c, quote_string() preserves carriage returns and newlines in marker-message, allowing report_attr() output to become scheduler PPD control lines. Execution as lp was demonstrated only with a Foomatic-backed queue and a later print job; OpenPrinting bounds CUPS-only impact to queue availability.

CVSS severity3.3
Low
EPSS probability0.18%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Status-line injection in OpenPrinting CUPS before 2.4.20 allows attackers to disrupt a print queue through a malicious IPP printer. In backend/ipp.c, quote_string() preserves carriage returns and newlines in marker-message, allowing report_attr() output to become scheduler PPD control lines. Execution as lp was demonstrated only with a Foomatic-backed queue and a later print job; OpenPrinting bounds CUPS-only impact to queue availability.

The record

CVE
CVE-2026-55453
Published
Oct 15, 2026
Updated
Oct 15, 2026
Vendor
OpenPrinting
Product
CUPS
Classifications
CWE-78, CWE-74, CWE-77, T1203
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 15, 2026CVE publishedPublication date reported by the CVE source.
  2. Oct 15, 2026Record 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=< 2.4.20

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

OpenPrinting · CUPSversion=< 2.4.20

Published CVSS scores

4.8SUSECVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N
3.3OpenPrinting / GitHub CNACVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L
5.3SUSECVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L

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.

Activity data is delayed. The latest report is Sep 28, 2026.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-78Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
CWE-74Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')
CWE-77Improper Neutralization of Special Elements used in a Command ('Command Injection')
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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