What is CVE-2026-19953?

CVE-2026-19953 is a security advisory published by Microsoft Security Response Center (MSRC) with Medium severity. URI versions before 5.36 for Perl encode non-NFC host names to non-standard punycode labels via missing normalization in nameprep

Which CVE IDs does CVE-2026-19953 cover?

CVE-2026-19953 covers the following CVE IDs: CVE-2026-19953. Each CVE has its own detail page on EchelonGraph Pulse with the synthesized EG score.

What is the CVSS v3 score of CVE-2026-19953?

CVE-2026-19953 has a CVSS v3 base score of 6.5, published by Microsoft Security Response Center (MSRC).

Which products are affected by CVE-2026-19953?

CVE-2026-19953 affects 2 products, including: azl3 perl-URI 5.21-2 on Azure Linux 3.0; azl3 perl-URI 5.21-3 on Azure Linux 3.0.

CVE-2026-19953MediumCVSS 6.5

URI versions before 5.36 for Perl encode non-NFC host names to non-standard punycode labels via missing normalization in nameprep

Vendor

Microsoft Security Response Center (MSRC)

Published

September 3, 2026

Last Modified

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🔗 CVE IDs covered (1)

CVE-2026-19953 →

🎯 Affected products2

azl3 perl-URI 5.21-2 on Azure Linux 3.0
azl3 perl-URI 5.21-3 on Azure Linux 3.0

✅ Remediation

Security Update — fixed build 5.21-3 KBRelease Notes (Security Update) — fixed build 5.21-3

🔗 References (2)

advisoryhttps://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-19953
patchhttps://learn.microsoft.com/en-us/azure/azure-linux/tutorial-azure-linux-upgrade