In the GNU C Library (aka glibc or libc6) before 2.28, parse_reg_exp in posix/regcomp.c…
Priority LOW 39CWE-19Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- No fix listed
Attack profile from CVSS 3.0 · NVD. Fix status from CNA and Red Hat.
Summary
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.
Why it matters now
EPSS 0.03906 90th percentileScored 2026-11-07
Public exploit Yes 4 exploit referencesTagged by NVD
Fix No fix listed No fixed version in the sources yet
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | — | all versions | — | No fix listed | CNA |
- — Vendor— Affected all versions Fixed in — No fix listed CNA
CPE configurations NVD · 4
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:gnu:glibc:*:*:*:*:*:*:*:* | before 2.28 | Vulnerable | GNU |
| cpe:2.3:a:netapp:cloud_backup:*:*:*:*:*:*:*:* | all versions | Vulnerable | NetApp |
| cpe:2.3:a:netapp:ontap_select_deploy_administration_utility:-:*:*:*:*:*:*:* | not specified by NVD | Vulnerable | NetApp |
| cpe:2.3:a:netapp:steelstore_cloud_integrated_storage:-:*:*:*:*:*:*:* | not specified by NVD | Vulnerable | NetApp |
- cpe:2.3:a:gnu:glibc:*:*:*:*:*:*:*:* Versions before 2.28 Vulnerable ·GNU
- cpe:2.3:a:netapp:cloud_backup:*:*:*:*:*:*:*:* Versions all versions Vulnerable ·NetApp
- cpe:2.3:a:netapp:ontap_select_deploy_administration_utility:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
- cpe:2.3:a:netapp:steelstore_cloud_integrated_storage:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
Remediation
No fixed version listed by the sources yet.
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 5 | Affected | No fix planned: Will not fix |
| Red Hat Enterprise Linux 6 | Affected | No fix planned: Will not fix |
| Red Hat Enterprise Linux 7 | Affected | No fix yet |
Timeline
- 2026-10-02 Threatist record created from CVE-2009-5155
- 2026-10-03 Alias added: GHSA-2p2p-xpf9-5p78
- 2026-10-07 EPSS moved to the 90th–95th percentile
References
Exploit 4
Patch 2
Other 5
- https://sourceware.org/git/gitweb.cgi?p=glibc.git%3Bh=eb04c21373e2a2885f3d52ff192b0499afe3c672
- https://support.f5.com/csp/article/K64119434
- https://support.f5.com/csp/article/K64119434?utm_source=f5support&%3Butm_medium=RSS
- [bookkeeper-issues] 20210628 [GitHub] [bookkeeper] padma81 opened a new issue #2746: Security Vulnerabilities in CentOS 7 image, Upgrade image to CentOS 8
- [bookkeeper-issues] 20210629 [GitHub] [bookkeeper] padma81 opened a new issue #2746: Security Vulnerabilities in CentOS 7 image, Upgrade image to CentOS 8
Sources
- CVE-2009-5155 · CVE Program
- CVE-2009-5155 · NVD
- FIRST EPSS
- GHSA-2p2p-xpf9-5p78 · GitHub Advisory Database · CC BY 4.0
- CVE-2009-5155 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences