Amazon Linux 2023 Security Advisory: ALAS2023-2026-3403
Advisory Released Date: 2026-11-09
Advisory Updated Date: 2026-11-09
Severity:
Medium
Issue Overview:
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
Issue Correction:
Run dnf update perl-URI --releasever 2023.12.20261109 or dnf update --advisory ALAS2023-2026-3403 --releasever 2023.12.20261109 to update your system.
More information on how to update your system can be found on this page: Amazon Linux 2023 documentation
New Packages:
noarch:
perl-URI-tests-5.18-1.amzn2023.0.2.noarch
perl-URI-5.18-1.amzn2023.0.2.noarch
src:
perl-URI-5.18-1.amzn2023.0.2.src