CVE-2026-0915
Published: 15 January 2026
Summary
CVE-2026-0915 is a high-severity Use of Uninitialized Resource (CWE-908) vulnerability in Gnu Glibc. Its CVSS base score is 7.5 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique DNS (T1071.004); ranked at the 6.8th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified are NIST 800-53 CM-6 (Configuration Settings) and SI-2 (Flaw Remediation).
Deeper analysis
CVE-2026-0915, published on 2026-01-15, affects the GNU C Library (glibc) versions 2.0 through 2.42. The vulnerability arises when the functions getnetbyaddr or getnetbyaddr_r are called with an nsswitch.conf configuration that specifies the library's DNS backend for network lookups, and the query targets a zero-valued network. This results in stack contents being leaked to the configured DNS resolver. It carries a CVSS v3.1 base score of 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N) and maps to CWE-908.
Remote attackers can exploit this vulnerability with low complexity, no required privileges, and no user interaction. Exploitation involves triggering the affected functions under the specified nsswitch.conf and network query conditions, enabling high confidentiality impact through the disclosure of stack memory contents transmitted to the DNS resolver.
Advisories and patches are detailed in the Sourceware Bugzilla entry at https://sourceware.org/bugzilla/show_bug.cgi?id=33802 and the OSS-Security mailing list post at http://www.openwall.com/lists/oss-security/2026/01/16/6.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-2855
Vulnerability details
Calling getnetbyaddr or getnetbyaddr_r with a configured nsswitch.conf that specifies the library's DNS backend for networks and queries for a zero-valued network in the GNU C Library version 2.0 to version 2.42 can leak stack contents to the configured DNS…
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resolver.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Vulnerability directly causes stack memory disclosure transmitted to the DNS resolver, enabling data exfiltration over DNS protocol.
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Flaw remediation directly mitigates the vulnerability by applying patches to affected glibc versions 2.0 through 2.42.
Configuration settings enforce secure nsswitch.conf to exclude the DNS backend for network lookups, preventing the trigger condition for stack leakage.
Monitoring for information disclosure detects anomalous DNS queries containing leaked stack contents from the vulnerable glibc functions.