CVE-2026-5358

Static data overwrite via unchecked NIS+ response length

Published Apr 20, 2026 · Updated Apr 20, 2026

Buffer overflow in nis_local_principal in GNU C Library 2.43 and earlier overwrites adjacent static data from a trusted NIS+ response. nis_local_principal passes the first NIS+ result value to strcpy without checking it against the NIS_MAXNAMELEN-sized static __principal buffer. The CNA rejected the CVE because Linux distributions never shipped NIS+ clients or servers and the cold-start cache restricts calls to a trusted server, so no security boundary is crossed.

CVSS severity6.5
Medium
EPSS probabilityUnavailable
No score available in this record
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Buffer overflow in nis_local_principal in GNU C Library 2.43 and earlier overwrites adjacent static data from a trusted NIS+ response. nis_local_principal passes the first NIS+ result value to strcpy without checking it against the NIS_MAXNAMELEN-sized static __principal buffer. The CNA rejected the CVE because Linux distributions never shipped NIS+ clients or servers and the cold-start cache restricts calls to a trusted server, so no security boundary is crossed.

The record

CVE
CVE-2026-5358
Published
Apr 20, 2026
Updated
Apr 20, 2026
Vendor
The GnuPG Project
Product
glibc
Classifications
Unavailable
Attack vector
Unavailable
Privileges
Unavailable

Timeline

How it unfolded

  1. Apr 20, 2026CVE publishedPublication date reported by the CVE source.
  2. Apr 20, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <=2.43

What conditions does exploitation require?

Attack vectorUnavailable in this record.
Required privilegesUnavailable in this record.

What is affected?

The GnuPG Project · glibcversion=0 <=2.43

Published CVSS scores

6.5Amazon LinuxCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:L

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
VectorUnavailable
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

No sourced classifications are available.

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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