CRITICAL🇵🇱 Wersja polska

CVE-2026-39821

CVSS 9.6v3.1pub. 2026-05-22upd. 2026-07-02

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 package. For example, a program which performs privilege checks on the ASCII hostname may reject "example.com" but permit "xn--example-.com". If that program subsequently converts the ASCII hostname to Unicode, it will inadvertently permits access to the Unicode name "example.com".

CVSS Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N
  • Golang Net

    APP
    Golang
    < 0.55.0
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CHECK WITH VENDOR
No clear patch data available. Check vendor references.
Tags
LPE
CWE
References

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