Amazon Linux 2 (EOS) Security Advisory: ALAS2-2026-4083
Advisory Released Date: 2026-11-09
Advisory Updated Date: 2026-11-09
URI::_idna::nameprep only lowercased the label and skipped the Unicode
normalization that RFC 3490/3491 require. As a result, a host that was
not already in NFC encoded to a non-standard A-label that disagrees with
what browsers, curl, Go, Java, and Python compute for the same input --
and that A-label does not round-trip. Code that reads $uri->host for a
security decision (allow/deny lists, SSRF filters, routing, dedup) could
therefore disagree with the host that is actually fetched. (CVE-2026-19953)
Affected Packages:
perl-URI
Note:
This advisory is applicable to Amazon Linux 2 (AL2) Core repository. Visit this FAQ section for the difference between AL2 Core and AL2 Extras advisories.
Issue Correction:
Run yum update perl-URI or yum update --advisory ALAS2-2026-4083 to update your system.
noarch:
perl-URI-1.60-9.amzn2.0.1.noarch
src:
perl-URI-1.60-9.amzn2.0.1.src