CVE-2009-5155: GNU Glibc

High severity, CVSS 7.5. EPSS: 3.9% chance of exploitation in the next 30 days.

In the GNU C Library (aka glibc or libc6) before 2.28, parse_reg_exp in posix/regcomp.c misparses alternatives, which allows attackers to cause a denial of service (assertion failure and application exit) or trigger an incorrect result by attempting a regular-expression match.

Affected products

• GNU Glibc: before 2.28 (fixed in 2.28)
• Netapp Cloud Backup: any version
• Netapp Ontap Select Deploy Administration Utility: affected versions not specified
• Netapp Steelstore Cloud Integrated Storage: affected versions not specified

Published 2019-02-26. Last modified 2026-06-16.