CVE-2026-19954

Net::Whois::Raw versions before 2.99044 for Perl ship a pwhois command-line tool that queries WHOIS for the wrong domain for unicode domain names. pwhois encodes each non-ASCII label directly using Net::IDN::Punycode and prepends xn--. Apart from lowercasing ASCII and Cyrillic letters, it skips the IDNA mapping and normalization steps, so a label with other uppercase letters, or not in NFC, encodes to a different A-label than its IDNA form. For example, a label of U+00C9 followed by "cole" encodes to "xn--cole-pka" rather than "xn--cole-9oa". The Net::Whois::Raw library modules are not affected.

CVSS v3 5.4 MEDIUM

5.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/regru/Net-Whois-Raw/issues/34
https://github.com/regru/Net-Whois-Raw/pull/35
https://metacpan.org/release/NALOBIN/Net-Whois-Raw-2.99044/changes
https://metacpan.org/release/PJCJ/Net-IDN-Encode-2.590-TRIAL/view/lib/Net/IDN/Punycode.pm#WARNING
https://security.metacpan.org/patches/N/Net-Whois-Raw/2.99043/CVE-2026-19954-r1.patch
https://www.rfc-editor.org/rfc/rfc5891#section-5.2
http://www.openwall.com/lists/oss-security/2026/10/05/9

Configurations

No configuration.

History

06 Oct 2026, 18:16

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 5.4

05 Oct 2026, 19:17

Type	Values Removed	Values Added
References		() http://www.openwall.com/lists/oss-security/2026/10/05/9 -

05 Oct 2026, 07:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-05 07:16

Updated : 2026-10-06 18:16

NVD link : CVE-2026-19954

Mitre link : CVE-2026-19954

CVE.ORG link : CVE-2026-19954

JSON object : View

Products Affected

No product.

CWE

CWE-176

Improper Handling of Unicode Encoding

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