DEBIAN-CVE-2026-87080

Source
https://security-tracker.debian.org/tracker/CVE-2026-87080
Import Source
https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-87080.json
JSON Data
https://api.osv.dev/v1/vulns/DEBIAN-CVE-2026-87080
Upstream
Published
2026-09-22T08:16:40Z
Modified
2026-09-23T05:01:13Z
Severity
  • 9.1 (Critical) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H CVSS Calculator
Summary
[none]
Details

Net::IDN::Punycode::PP versions before 2.590 for Perl decode a truncated label to a name containing a character it never encoded in decode_punycode. The pure-Perl decoder reads one digit at a time with four-argument substr and tests the result with defined to detect the end of the input. substr on an exhausted string returns the empty string rather than undef, so decoding continues past the end. The empty string converts to a digit value below the range, reducing the accumulator, and the decoder derives one extra code point and its position from it. The result is deterministic. The XS backend rejects the same label. Net::IDN::Punycode uses this backend wherever the XS does not build. The two backends disagree about what such a label means, so a sender can pick a label that one installation resolves to a name and another rejects.

References

Affected packages

Debian:12 / libnet-idn-encode-perl

Package

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

Affected ranges

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

Affected versions

2.*
2.500-3
2.500-5

Ecosystem specific

{
    "urgency":  "not yet assigned"
}

Database specific

source
"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-87080.json"

Debian:13 / libnet-idn-encode-perl

Package

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

Affected ranges

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

Affected versions

2.*
2.500-5

Ecosystem specific

{
    "urgency":  "not yet assigned"
}

Database specific

source
"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-87080.json"

Debian:14 / libnet-idn-encode-perl

Package

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

Affected ranges

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

Affected versions

2.*
2.500-5

Ecosystem specific

{
    "urgency":  "not yet assigned"
}

Database specific

source
"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-87080.json"