UBUNTU-CVE-2026-87081

Source
https://ubuntu.com/security/CVE-2026-87081
Import Source
https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-87081.json
JSON Data
https://api.osv.dev/v1/vulns/UBUNTU-CVE-2026-87081
Upstream
Published
2026-09-22T08:16:00Z
Modified
2026-09-24T02:00:38Z
Severity
  • 7.5 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
  • Ubuntu - medium
Summary
[none]
Details

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.

References

Affected packages

Ubuntu:16.04:LTS
libnet-idn-encode-perl

Package

Name
libnet-idn-encode-perl
Purl
pkg:deb/ubuntu/libnet-idn-encode-perl?arch=source&distro=xenial

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected

Affected versions

2.*
2.202-1
2.300-1
2.300-1build1

Ecosystem specific

{
    "binaries":  [
        {
            "binary_name":  "libnet-idn-encode-perl",
            "binary_version":  "2.300-1build1"
        }
    ]
}

Database specific

source
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-87081.json"
Ubuntu:18.04:LTS
libnet-idn-encode-perl

Package

Name
libnet-idn-encode-perl
Purl
pkg:deb/ubuntu/libnet-idn-encode-perl?arch=source&distro=bionic

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected

Affected versions

2.*
2.400-1build1

Ecosystem specific

{
    "binaries":  [
        {
            "binary_name":  "libnet-idn-encode-perl",
            "binary_version":  "2.400-1build1"
        }
    ]
}

Database specific

source
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-87081.json"
Ubuntu:20.04:LTS
libnet-idn-encode-perl

Package

Name
libnet-idn-encode-perl
Purl
pkg:deb/ubuntu/libnet-idn-encode-perl?arch=source&distro=focal

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected

Affected versions

2.*
2.500-1
2.500-1build1

Ecosystem specific

{
    "binaries":  [
        {
            "binary_name":  "libnet-idn-encode-perl",
            "binary_version":  "2.500-1build1"
        }
    ]
}

Database specific

source
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-87081.json"
Ubuntu:22.04:LTS
libnet-idn-encode-perl

Package

Name
libnet-idn-encode-perl
Purl
pkg:deb/ubuntu/libnet-idn-encode-perl?arch=source&distro=jammy

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected

Affected versions

2.*
2.500-1build2
2.500-2
2.500-2build1

Ecosystem specific

{
    "binaries":  [
        {
            "binary_name":  "libnet-idn-encode-perl",
            "binary_version":  "2.500-2build1"
        }
    ]
}

Database specific

source
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-87081.json"
Ubuntu:24.04:LTS
libnet-idn-encode-perl

Package

Name
libnet-idn-encode-perl
Purl
pkg:deb/ubuntu/libnet-idn-encode-perl?arch=source&distro=noble

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected

Affected versions

2.*
2.500-3
2.500-3build1
2.500-3build2
2.500-5

Ecosystem specific

{
    "binaries":  [
        {
            "binary_name":  "libnet-idn-encode-perl",
            "binary_version":  "2.500-5"
        }
    ]
}

Database specific

source
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-87081.json"
Ubuntu:26.04:LTS
libnet-idn-encode-perl

Package

Name
libnet-idn-encode-perl
Purl
pkg:deb/ubuntu/libnet-idn-encode-perl?arch=source&distro=resolute

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected

Affected versions

2.*
2.500-5build1

Ecosystem specific

{
    "binaries":  [
        {
            "binary_name":  "libnet-idn-encode-perl",
            "binary_version":  "2.500-5build1"
        }
    ]
}

Database specific

source
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-87081.json"