Skip to content
Fencer Vulns
medium 4.3

CVE-2026-87875 json

Cups: openprinting cups: heap out-of-bounds read in cupsutf32toutf8() via missing source-length bound

published 2026-09-09 2 mo ago modified 2026-11-06 3 d ago also EUVD-2026-75085

cvss
4.3
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.4%
EPSS 0.4% chance of exploitation in 30 days, percentile 33%
public exploits
0
none known

Summary

The cupsUTF32ToUTF8() function in CUPS's cups/transcode.c lacks a source-length bound and can read past the end of the source buffer, resulting in a heap out-of-bounds read. This is reachable via SNMP supply-description parsing in backend/snmp-supplies.c with attacker-controlled content.

Patch / fix

  • Red Hat Red Hat Hardened Images 2.4.19-4.1.hum1
  • cups hummingbird 1 2.4.19-4.1.hum1
  • cups-lpd hummingbird 1 2.4.19-4.1.hum1
  • cups-libs hummingbird 1 2.4.19-4.1.hum1
  • cups-client hummingbird 1 2.4.19-4.1.hum1
  • cups-ipptool hummingbird 1 2.4.19-4.1.hum1
  • cups-filesystem hummingbird 1 2.4.19-4.1.hum1
  • cups-printerapp hummingbird 1 2.4.19-4.1.hum1

red hat advisories RHSA-2026:66600

  • cups SLE Module for Development Tools 15 SP7, SLE Module for Desktop Applications 15 SP7, SLE Module for Basesystem 15 SP7 +3 more 2.2.7-150000.3.96.1
  • cups Linux Micro 6.0 2.4.19-2.1
  • cups Linux Micro 6.1 2.4.19-slfo.1.1_2.1
  • cups SLES LTSS Extended Security 12 SP5 1.7.5-20.70.1

suse advisories SUSE-SU-2026:4281-1SUSE-SU-2026:23877-1SUSE-SU-2026:23925-1SUSE-SU-2026:4216-1

  • cups openSUSE Leap 16.0 2.4.19-160000.2.1
  • cups openSUSE Tumbleweed 2.4.19-3.1

opensuse advisories openSUSE-SU-2026:21893-1openSUSE-SU-2026:11785-1

  • cups Azure Linux 3.0 2.4.19-2

azure linux advisories AZL-100920

Azure Linux vulnerability data, Copyright (c) Microsoft Corporation, from https://github.com/microsoft/AzureLinuxVulnerabilityData via OSV, under the MIT licence; changed: normalised to fixed package versions per release. MIT

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-87875 updated cvss 4.3

cups: OpenPrinting CUPS: Heap out-of-bounds read in cupsUTF32ToUTF8() via missing source-length bound

  • Red Hat Enterprise Linux 6 cups, cups-lpd, cups-php, cups-libs, cups 2.4.10-18.el10_2 Red Hat Enterprise Linux 7 cups, cups-lpd, cups-libs, cups-client, cups-ipptool, cups-filesystem, +1 more Red Hat Enterprise Linux 8 cups, cups-lpd, cups-libs, cups-client, cups-ipptool, cups-filesystem, +1 more Red Hat Enterprise Linux 9 cups, cups-lpd, cups-libs, rhel9/cups, cups-client, cups-ipptool, +3 more Red Hat Enterprise Linux 10 cups 2.4.10-18.el10_2 Red Hat OpenShift Container Platform 4 openshift/ose-rhel-coreos-8
    affected: workaround, no fix available “Fixed on upstream master branch with commit 0c6842f and for versions 2.4.x with commit 2b1dc17.”
  • Red Hat Hardened Images cups 2.4.19-4.1.hum1, cups-lpd 2.4.19-4.1.hum1, cups-libs 2.4.19-4.1.hum1, cups-client 2.4.19-4.1.hum1, cups-ipptool 2.4.19-4.1.hum1, cups-filesystem 2.4.19-4.1.hum1, +1 more
    fixed: vendor fix “Fixed on upstream master branch with commit 0c6842f and for versions 2.4.x with commit 2b1dc17.” RHSA-2026:66600

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
Proof of concept is public
Automatable
no
Technical impact
partial
Assessed
2 mo ago

Exploit prediction

0.39% chance of exploitation in the next 30 days, higher than 33% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • github.com https://github.com/OpenPrinting/cups/security/advisories/GHSA-559w-7676-3xrq referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 4.3 CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Affected products

  • Red Hat Red Hat Hardened Images
  • Red Hat Red Hat Enterprise Linux 10
  • Red Hat Red Hat Enterprise Linux 6
  • Red Hat Red Hat Enterprise Linux 7
  • Red Hat Red Hat Enterprise Linux 8
  • Red Hat Red Hat Enterprise Linux 9
  • Red Hat Red Hat OpenShift Container Platform 4

Classification

Weakness

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.