GHSA-2XF4-CG6J-VHGQ symfony/polyfill-intl-idn: xn-- labels with ASCII-only Punycode payloads are treated as equivalent to their decoded form

Description symfony/polyfill-intl-idn provides a userland implementation of idntoutf8 and idntoascii for runtimes that lack the intl extension. Its Idn::process method decodes labels prefixed with xn-- using Punycode but never enforces the validity criterion added in UTS 46 revision 33 Section 4...

symfony/polyfill-intl-idn: xn-- labels with ASCII-only Punycode payloads are treated as equivalent to their decoded form

Description symfony/polyfill-intl-idn provides a userland implementation of idntoutf8 and idntoascii for runtimes that lack the intl extension. Its Idn::process method decodes labels prefixed with xn-- using Punycode but never enforces the validity criterion added in UTS 46 revision 33 Section 4...

SUSE CVE-2026-39821

The ToASCII and ToUnicode functions incorrectly accept Punycode-encoded labels that decode to an ASCII-only label. For example, ToUnicode"xn--example-.com" incorrectly returns the name "example.com" rather than an error. This behavior can lead to privilege escalation in programs using the idna...

Invoking failure to reject ASCII-only Punycode-encoded labels in golang.org/x/net/idna

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Linux Distros Unpatched Vulnerability : CVE-2026-39821

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available. - The ToASCII and ToUnicode functions incorrectly accept Punycode-encoded labels that decode to an ASCII- only label. For example, ToUnicodexn--example-.com...

Incorrect Comparison

Overview Affected versions of this package are vulnerable to Incorrect Comparison in the process function in Idn.php, which does not necessarily treat xn-- labeled input as punycode, if it contains only ASCII. This case was overlooked in the specification until UTS 46 revision 33, when it was...

CVE-2026-46644: symfony/polyfill-intl-idn accepts xn-- labels whose Punycode payload decodes to ASCII-only: insecure equivalence

More info at https://symfony.com/cve-2026-46644...

CVE-2026-46644: symfony/polyfill-intl-idn accepts xn-- labels whose Punycode payload decodes to ASCII-only: insecure equivalence

More info at https://symfony.com/cve-2026-46644...

Improper Authentication

Overview Affected versions of this package are vulnerable to Improper Authentication via the ToASCII and ToUnicode functions. An attacker can bypass hostname validation by submitting Punycode-encoded labels that decode to ASCII-only labels, potentially leading to privilege escalation in...

Improper Authentication

Overview Affected versions of this package are vulnerable to Improper Authentication via the ToASCII and ToUnicode functions. An attacker can bypass hostname validation by submitting Punycode-encoded labels that decode to ASCII-only labels, potentially leading to privilege escalation in...

AZL-87834 CVE-2026-39821 affecting package jx for versions less than 3.10.182-4

The ToASCII and ToUnicode functions incorrectly accept Punycode-encoded labels that decode to an ASCII-only label. For example, ToUnicode"xn--example-.com" incorrectly returns the name "example.com" rather than an error. This behavior can lead to privilege escalation in programs using the idna...

AZL-87792 CVE-2026-39821 affecting package golang for versions less than 1.25.11-3

The ToASCII and ToUnicode functions incorrectly accept Punycode-encoded labels that decode to an ASCII-only label. For example, ToUnicode"xn--example-.com" incorrectly returns the name "example.com" rather than an error. This behavior can lead to privilege escalation in programs using the idna...

AZL-87804 CVE-2026-39821 affecting package ignition-flatcar for versions less than 2.22.0-5

The ToASCII and ToUnicode functions incorrectly accept Punycode-encoded labels that decode to an ASCII-only label. For example, ToUnicode"xn--example-.com" incorrectly returns the name "example.com" rather than an error. This behavior can lead to privilege escalation in programs using the idna...

AZL-87266 CVE-2026-39821 affecting package kata-containers-preview 3.27.0~preview2-2

The ToASCII and ToUnicode functions incorrectly accept Punycode-encoded labels that decode to an ASCII-only label. For example, ToUnicode"xn--example-.com" incorrectly returns the name "example.com" rather than an error. This behavior can lead to privilege escalation in programs using the idna...

AZL-98583 CVE-2026-39821 affecting package golang 1.27.1-1

The ToASCII and ToUnicode functions incorrectly accept Punycode-encoded labels that decode to an ASCII-only label. For example, ToUnicode"xn--example-.com" incorrectly returns the name "example.com" rather than an error. This behavior can lead to privilege escalation in programs using the idna...

AZL-87726 CVE-2026-39821 affecting package etcd for versions less than 3.5.30-2

The ToASCII and ToUnicode functions incorrectly accept Punycode-encoded labels that decode to an ASCII-only label. For example, ToUnicode"xn--example-.com" incorrectly returns the name "example.com" rather than an error. This behavior can lead to privilege escalation in programs using the idna...

AZL-87873 CVE-2026-39821 affecting package kube-vip-cloud-provider for versions less than 0.0.10-6

The ToASCII and ToUnicode functions incorrectly accept Punycode-encoded labels that decode to an ASCII-only label. For example, ToUnicode"xn--example-.com" incorrectly returns the name "example.com" rather than an error. This behavior can lead to privilege escalation in programs using the idna...

AZL-88248 CVE-2026-39821 affecting package prometheus-node-exporter for versions less than 1.7.0-4

The ToASCII and ToUnicode functions incorrectly accept Punycode-encoded labels that decode to an ASCII-only label. For example, ToUnicode"xn--example-.com" incorrectly returns the name "example.com" rather than an error. This behavior can lead to privilege escalation in programs using the idna...

AZL-87573 CVE-2026-39821 affecting package cri-tools for versions less than 1.32.0-6

The ToASCII and ToUnicode functions incorrectly accept Punycode-encoded labels that decode to an ASCII-only label. For example, ToUnicode"xn--example-.com" incorrectly returns the name "example.com" rather than an error. This behavior can lead to privilege escalation in programs using the idna...

AZL-87146 CVE-2026-39821 affecting package azl-otel-collector 0.127.0-1

The ToASCII and ToUnicode functions incorrectly accept Punycode-encoded labels that decode to an ASCII-only label. For example, ToUnicode"xn--example-.com" incorrectly returns the name "example.com" rather than an error. This behavior can lead to privilege escalation in programs using the idna...