Vulnerability · Published Oct 5, 2026 · Assigned by CPANSec
CVE-2026-19954Net::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
Medium 5.4
In plain English
A medium-severity security flaw in Net-Whois-Raw. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 14% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | libnet-whois-raw-perl | no fix listed | DEBIAN-CVE-2026-19954 |
| Debian:13 | libnet-whois-raw-perl | no fix listed | DEBIAN-CVE-2026-19954 |
| Debian:14 | libnet-whois-raw-perl | 2.99043-2 | DEBIAN-CVE-2026-19954 |
| Ubuntu:22.04:LTS | libnet-whois-raw-perl | no fix listed | UBUNTU-CVE-2026-19954 |
| Ubuntu:24.04:LTS | libnet-whois-raw-perl | no fix listed | UBUNTU-CVE-2026-19954 |
| Ubuntu:26.04:LTS | libnet-whois-raw-perl | no fix listed | UBUNTU-CVE-2026-19954 |
| Ubuntu:26.10 | libnet-whois-raw-perl | no fix listed | UBUNTU-CVE-2026-19954 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Net-Whois-Raw | 0 – before 2.99044 |
Weakness: CWE-176 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
References
- https://metacpan.org/release/NALOBIN/Net-Whois-Raw-2.99044/changes release-notes
- https://security.metacpan.org/patches/N/Net-Whois-Raw/2.99043/CVE-2026-19954-r1.patch patch
- https://github.com/regru/Net-Whois-Raw/issues/34 issue-tracking
- https://github.com/regru/Net-Whois-Raw/pull/35 issue-tracking
- https://metacpan.org/release/PJCJ/Net-IDN-Encode-2.590-TRIAL/view/lib/Net/IDN/Punycode.pm#WARNING
- https://www.rfc-editor.org/rfc/rfc5891#section-5.2 technical-description
- http://www.openwall.com/lists/oss-security/2026/10/05/9