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CVE-2026-87078

Net::IDN::Punycode versions from 2.302 before 2.590 for Perl leak the output buffer on every rejected label in decode_punycode

Published
Last modified
published
Not listed in CISA KEV
Fix
Fixed in 2.590
None on Exploit-DB, Metasploit or GitHub
  • Exploitation: none
  • Automatable: yes
  • Technical impact: partial

Summary

Net::IDN::Punycode versions from 2.302 before 2.590 for Perl leak the output buffer on every rejected label in decode_punycode. The XS backend allocates the scalar it returns before it validates the input, sizing the buffer at twice the input length. The scalar is released only on the success path, so each of the three croaks that reject a label leaves the scalar and its buffer allocated. Nothing bounds the label length in the to-Unicode direction, since the 63-byte DNS limit is checked only when converting to ASCII. Only the XS backend is affected. A sender who supplies invalid labels grows the process by twice the label length per rejected call, with no successful call needed.

Timeline

  1. CVE published
  2. CISA SSVC assessment

    Exploitation: none · Automatable: yes · Technical impact: partial

  3. Record last updated

Affected versions

  • Net-IDN-Encode

    From 2.302 · fixed in 2.590

References 3

metacpan.org

GitHub · robrwo/Net-IDN-Encode