CVE-2026-87079: Net::IDN::Punycode versions before 2.590 for Perl allow CPU exhaustion via quadratic insertion cost when decoding a long label in decode_punycode
Perl Net::IDN::Punycode before 2.590 can exhaust CPU decoding a long Punycode label.
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Vulnerability1 · 1 read
CVE-2026-87079
Unauthenticated RCE in Dell Secure Connect Gateway 5.0 (CVE-2026-87079)
- CVSS 3.1
- 7.5 high
- EPSS
- —
- Published
- ·
- Modified
AI analysisSummaries by Vani AI
The CVE allows CPU exhaustion in Dell Secure Connect Gateways using long Perl labels, with a high CVSS score. It was disclosed but no public PoC exists.
What to do: Upgrade to the latest version to eliminate CPU exhaustion. Check for any plugins with large active installs. Consider updating firewall rules or service configurations.
| Product | Affected |
|---|---|
| Dell Secure Connect Gateway 5.0 | 5.0 |
| Dell Secure Connect Gateway 4.0 | 4.0 |
Estimated exposure
moderateNo basis for an estimate.
Order-of-magnitude estimate by the model from install counts, market share and public scan data it knows; verify before quoting.
Description · NVD
Net::IDN::Punycode versions before 2.590 for Perl allow CPU exhaustion via quadratic insertion cost when decoding a long label in decode_punycode. The XS backend inserts each decoded code point into a UTF-8 buffer and finds the insertion point by scanning that buffer from the start, one character at a time. The scan runs once per code point over the output built so far, so the cost is quadratic in the label length. The pure-Perl backend downgrades its input to bytes so that substr can index it directly, but takes its working copy before the downgrade, so when the input carries the UTF-8 flag every substr on the copy scans from the start, with the same quadratic cost. Nothing bounds the label length in the to-Unicode direction. The 63-byte DNS limit is checked only when converting to ASCII, so domain_to_unicode and uts46_to_unicode pass an attacker-supplied label of any length to the decoder.
- Weakness
- CWE-407
- Vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H