CVE-2026-87876 (CVSS 3)

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.

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CVSS v3.1 Score

3.0

LOW

CVSS:3.1/AV:A/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:N

EPSS — Exploit Prediction

0.0039

Probability of exploitation

0.33%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-178 CWE-178

References

Other References

https://access.redhat.com/security/cve/CVE-2026-87876 https://bugzilla.redhat.com/show_bug.cgi?id=2530991 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 https://github.com/OpenPrinting/cups/security/advisories/GHSA-r8jp-q6fh-g5r2

Frequently Asked Questions

What is CVE-2026-87876? +

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. It has a CVSS v3.1 base score of 3.0 (LOW).

How severe is CVE-2026-87876? +

CVE-2026-87876 has a CVSS v3.1 score of 3.0 out of 10, rated LOW. This is a low-severity vulnerability with limited impact. The EPSS score is 0.0039, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-87876? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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CVE-2026-87876