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Vulnerability record · CVE-2026-1858 · published 29 April 2026

CVE-2026-1858: Gnu wget2 improper input validation vulnerability

Gnu · Wget2

wget2 accepts a server certificate with incorrect Key Usage (KU) or Extended Key Usage (EKU). If the attackers compromise a certificate (with the associated private key) issued for a different purpose, they may be able to reuse it for TLS server authentication.

4.8 CVSS 3.1 Medium EPSS 0.16% · top 96.0% CWE-20 · Improper input validation
4.8CVSS 3.1 base score
0.16%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
1References, 1 tagged exploit
17 Jun 2026Last modified by NVD

Description

wget2 accepts a server certificate with incorrect Key Usage (KU) or Extended Key Usage (EKU). If the attackers compromise a certificate (with the associated private key) issued for a different purpose, they may be able to reuse it for TLS server authentication.

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://www.tenable.com/security/research/tra-2026-37 ExploitThird Party Advisory

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2026-1858), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.