AZL-87387
See a problem?- Import Source
- https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-87387.json
- JSON Data
- https://api.osv.dev/v1/vulns/AZL-87387
- Upstream
- Published
- 2026-05-22T16:16:20Z
- Modified
- 2026-08-28T17:48:04Z
- Summary
- CVE-2026-39821 affecting package azurelinux-image-tools for versions less than 1.4.0-2
- Details
-
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".
- References