UBUNTU-CVE-2026-87079

See a problem?
Please try reporting it to the source first.
Source
https://ubuntu.com/security/CVE-2026-87079
Import Source
https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-87079.json
JSON Data
https://api.osv.dev/v1/vulns/UBUNTU-CVE-2026-87079
Upstream
Published
2026-09-22T00:00:00Z
Modified
2026-09-22T22:58:27Z
Severity
  • Ubuntu - medium
Summary
[none]
Details

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.

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-2026-87079.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-2026-87079.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-2026-87079.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-2026-87079.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-2026-87079.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-2026-87079.json"