How severe is CVE-2015-20109?

CVE-2015-20109 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2015-20109 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (24th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2015-20109?

CVE-2015-20109 affects Gnu Glibc. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2015-20109?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2015-20109 published?

CVE-2015-20109 was published on 2023-06-25 and last updated on 2026-06-17.

CVE-2015-20109

CVE-2015-20109 is a medium-severity vulnerability in Gnu Glibc with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-120.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
EPSS exploit prediction: 0% (24th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-120
Affected product: Gnu Glibc
Published: 2023-06-25
Last modified: 2026-06-17

Description

end_pattern (called from internal_fnmatch) in the GNU C Library (aka glibc or libc6) before 2.22 might allow context-dependent attackers to cause a denial of service (application crash), as demonstrated by use of the fnmatch library function with the **(!() pattern. NOTE: this is not the same as CVE-2015-8984; also, some Linux distributions have fixed CVE-2015-8984 but have not fixed this additional fnmatch issue.

Frequently asked questions

What is CVE-2015-20109?: end_pattern (called from internal_fnmatch) in the GNU C Library (aka glibc or libc6) before 2.22 might allow context-dependent attackers to cause a denial of service (application crash), as demonstrated by use of the fnmatch library function with the **(!() pattern. NOTE: this is not the same as CVE-2015-8984; also, some Linux distributions have fixed CVE-2015-8984 but have not fixed this additional fnmatch issue.
How severe is CVE-2015-20109?: CVE-2015-20109 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2015-20109 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (24th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2015-20109?: CVE-2015-20109 affects Gnu Glibc. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2015-20109?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2015-20109 published?: CVE-2015-20109 was published on 2023-06-25 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:gnu:glibc:*:*:*:*:*:*:*:*

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