DEBIAN-CVE-2026-87079
- Source
- https://security-tracker.debian.org/tracker/CVE-2026-87079
- Import Source
- https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-87079.json
- JSON Data
- https://api.osv.dev/v1/vulns/DEBIAN-CVE-2026-87079
- Upstream
- Published
- 2026-09-22T08:16:40Z
- Modified
- 2026-09-23T05:01:22Z
- 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
- 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
Debian:12 / libnet-idn-encode-perl
Package
- Name
- libnet-idn-encode-perl
- Purl
- pkg:deb/debian/libnet-idn-encode-perl?arch=source&distro=bookworm
Debian:13 / libnet-idn-encode-perl
Package
- Name
- libnet-idn-encode-perl
- Purl
- pkg:deb/debian/libnet-idn-encode-perl?arch=source&distro=trixie
Debian:14 / libnet-idn-encode-perl
Package
- Name
- libnet-idn-encode-perl
- Purl
- pkg:deb/debian/libnet-idn-encode-perl?arch=source&distro=forky