CVE-2026-1858 PUBLISHED

wget2 Improper Certificate Validation

Assigner: tenable
Reserved: 03.02.2026 Published: 29.04.2026 Updated: 29.04.2026

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.

Metrics

CVSS 3.1

CVSS Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N
CVSS Score: 4.8

Attack Vector	Network	Scope	Unchanged
Attack Complexity	High	Confidentiality Impact	Low
Privileges Required	None	Integrity Impact	Low
User Interaction	None	Availability Impact	None

CVSS 3.1

Product Status

Vendor	gnu
Product	wget2
Versions	Default: unaffected affected from 0 to 2.2.1 (incl.)

Credits

Ireneusz Pastusiak with Tenable finder

References

https://www.tenable.com/security/research/tra-2026-37

Problem Types

CWE-20 Improper input validation CWE

Impacts

CAPEC-21 Exploitation of Trusted Identifiers