
CVE catalog
CVE-2026-87081
Net::IDN::UTS46 versions before 2.590 for Perl allow CPU exhaustion via quadratic punycode encoding of an overlong label before the length check in to_ascii. to_ascii punycode encodes each label and
- Severity
- High · CVSS 7.5
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Published
- Updated
- Source
- [NVD] · [CVE record]
- EPSS
- 0.38% · Oct 25, 2026
Net::IDN::UTS46 versions before 2.590 for Perl allow CPU exhaustion via quadratic punycode encoding of an overlong label before the length check in to_ascii. to_ascii punycode encodes each label and only then applies the 63-byte DNS limit. encode_punycode in both backends follows the sample implementation in RFC 3492, whose outer loop runs once per distinct non-ASCII code point and scans the whole input each round, so a label of distinct non-ASCII characters costs the square of its length before the limit rejects it. Every ASCII conversion in the distribution, including domain_to_ascii and email_to_ascii, goes through to_ascii.
Vulnerable and fixed packages
Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.
| Distribution | Package | Release | Version | Status |
|---|---|---|---|---|
| Debian | libnet-idn-encode-perl | sid | 2.502-1 | vulnerable |
| Debian | libnet-idn-encode-perl | forky | 2.502-1 | vulnerable |
| Debian | libnet-idn-encode-perl | trixie | 2.500-5 | vulnerable |
| Debian | libnet-idn-encode-perl | bookworm | 2.500-3 | vulnerable |
Fixed-version evidence
| Distribution | Package | Type | Release | Fixed version | Urgency | Origin | Bugs |
|---|---|---|---|---|---|---|---|
| Debian | libnet-idn-encode-perl | source | sid | (unfixed) | not yet assigned | Not reported | [1148729] |
| Debian | libnet-idn-encode-perl | source | forky | (unfixed) | not yet assigned | Not reported | [1148729] |
| Debian | libnet-idn-encode-perl | source | trixie | (unfixed) | not yet assigned | Not reported | [1148729] |
| Debian | libnet-idn-encode-perl | source | bookworm | (unfixed) | not yet assigned | Not reported | [1148729] |
OpenFactory catalog packages
[Debian 12 (Bookworm)]
- [libnet-idn-encode-perl]Affected
Source package: [libnet-idn-encode-perl]
Details (2)
2.500-3+b1· amd64 · bookwormAffected
nvd · libnet-idn-encode-perl · debian · bookworm; nvd · libnet-idn-encode-perl · debian · 12
2.500-3+b1· arm64 · bookwormAffected
nvd · libnet-idn-encode-perl · debian · bookworm; nvd · libnet-idn-encode-perl · debian · 12
[Debian 13 (Trixie)]
- [libnet-idn-encode-perl]Affected
Source package: [libnet-idn-encode-perl]
Details (2)
2.500-5+b1· amd64 · trixieAffected
nvd · libnet-idn-encode-perl · debian · 13
2.500-5+b1· arm64 · trixieAffected
nvd · libnet-idn-encode-perl · debian · 13
Observed: