CVE-2026-1858

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 v3 4.8 MEDIUM

4.8^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://www.tenable.com/security/research/tra-2026-37	Exploit Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:gnu:wget2:*:*:*:*:*:*:*:*

History

26 Oct 2026, 20:10

Type	Values Removed	Values Added
Summary		(es) wget2 acepta un certificado de servidor con uso de clave (KU) incorrecto o uso de clave extendido (EKU). Si los atacantes comprometen un certificado (con la clave privada asociada) emitido para un propósito diferente, podrían reutilizarlo para autenticación de servidor TLS.

Information

Published : 2026-04-29 21:16

Updated : 2026-10-26 20:10

NVD link : CVE-2026-1858

Mitre link : CVE-2026-1858

CVE.ORG link : CVE-2026-1858

JSON object : View

Products Affected

gnu

wget2

CWE

CWE-20

Improper Input Validation

{"id": "CVE-2026-1858", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-1858", "role": "CISA Coordinator", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "version": "2.0.3", "timestamp": "2026-04-30T13:16:18.594329Z"}}], "cvssMetricV31": [{"type": "Secondary", "source": "vulnreport@tenable.com", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 4.8, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N", "integrityImpact": "LOW", "userInteraction": "NONE", "attackComplexity": "HIGH", "availabilityImpact": "NONE", "privilegesRequired": "NONE", "confidentialityImpact": "LOW"}, "impactScore": 2.5, "exploitabilityScore": 2.2}]}, "affected": [{"source": "vulnreport@tenable.com", "affectedData": [{"vendor": "gnu", "product": "wget2", "versions": [{"status": "affected", "version": "0", "versionType": "semver", "lessThanOrEqual": "2.2.1"}], "defaultStatus": "unaffected"}]}], "published": "2026-04-29T21:16:20.513", "references": [{"url": "https://www.tenable.com/security/research/tra-2026-37", "tags": ["Exploit", "Third Party Advisory"], "source": "vulnreport@tenable.com"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Secondary", "source": "vulnreport@tenable.com", "description": [{"lang": "en", "value": "CWE-20"}]}], "descriptions": [{"lang": "en", "value": "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."}, {"lang": "es", "value": "wget2 acepta un certificado de servidor con uso de clave (KU) incorrecto o uso de clave extendido (EKU). Si los atacantes comprometen un certificado (con la clave privada asociada) emitido para un prop\u00f3sito diferente, podr\u00edan reutilizarlo para autenticaci\u00f3n de servidor TLS."}], "lastModified": "2026-10-26T20:10:00.160", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:gnu:wget2:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "7059A7C4-12BD-4BA5-B6A7-642161B8DDA2", "versionEndIncluding": "2.2.1"}], "operator": "OR"}]}], "sourceIdentifier": "vulnreport@tenable.com"}