Vulnerability · Published Sep 9, 2026 · Assigned by redhat
CVE-2026-87876Cups: openprinting cups: remaining case-insensitive username matching in scheduler side paths (cve-2026-27447 follow-up)
Low 3.0
In plain English
A low-severity security flaw in Red Hat Enterprise Linux 10 from Red Hat. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 26% of all known vulnerabilities).
Severity (CVSS 3.1)3.0Low
Exploit odds (30 days)0.3%top 74.0% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known
Official description
Two case-insensitive comparisons on request-derived usernames outside the main authorization path in CUPS's scheduler (printer ACL validation and private-attribute filtering) could allow bypass of username-based access controls in certain configurations.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | cups | no fix listed | DEBIAN-CVE-2026-87876 |
| Debian:13 | cups | no fix listed | DEBIAN-CVE-2026-87876 |
| Debian:14 | cups | no fix listed | DEBIAN-CVE-2026-87876 |
| Ubuntu:22.04:LTS | cups | no fix listed | UBUNTU-CVE-2026-87876 |
| Ubuntu:24.04:LTS | cups | no fix listed | UBUNTU-CVE-2026-87876 |
| Ubuntu:26.04:LTS | cups | no fix listed | UBUNTU-CVE-2026-87876 |
| Ubuntu:26.10 | cups | no fix listed | UBUNTU-CVE-2026-87876 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Red Hat | Red Hat Hardened Images | see references |
| Red Hat | Red Hat Enterprise Linux 10 | see references |
| Red Hat | Red Hat Enterprise Linux 6 | see references |
| Red Hat | Red Hat Enterprise Linux 7 | see references |
| Red Hat | Red Hat Enterprise Linux 8 | see references |
| Red Hat | Red Hat Enterprise Linux 9 | see references |
| Red Hat | Red Hat Enterprise Linux 9 | see references |
| Red Hat | Red Hat OpenShift Container Platform 4 | see references |
Weakness: CWE-178 · Vector: CVSS:3.1/AV:A/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:N
References
- RHSA-2026:67568 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/security/cve/CVE-2026-87876 vdb-entry, x_refsource_REDHAT
- RHBZ#2530991 issue-tracking, x_refsource_REDHAT
- https://github.com/OpenPrinting/cups/commit/88e67c00c130a45f3a1edf36686f7a0b2982fef8
- https://github.com/OpenPrinting/cups/commit/f56844dbe4a54a9f8e1aeb3b913fbee614156bdb
- https://github.com/OpenPrinting/cups/security/advisories/GHSA-r8jp-q6fh-g5r2