DEBIAN-CVE-2026-64194
- Source
- https://security-tracker.debian.org/tracker/CVE-2026-64194
- Import Source
- https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-64194.json
- JSON Data
- https://api.osv.dev/v1/vulns/DEBIAN-CVE-2026-64194
- Upstream
- Published
- 2026-07-20T19:17:30Z
- Modified
- 2026-09-14T17:03:45Z
- 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::DNS versions through 1.55 for Perl allow Denial of Service via deep DNS compression pointer chains. Net::DNS::DomainName::decode follows RFC 1035 compression pointers by recursing into itself with no depth limit. It is possible to construct a name which saturates the call stack (at least with larger TCP responses), leading to a potential Denial of Service. The guard
$link < $offsetprevents forward and circular chains, but still allows arbitrarily long backward chains. The per-offset cache ($cache) is populated at the start of each call and short-circuits only re-traverses of the same offset - the initial descent through a fresh chain still recurses at full depth. A crafted packet can chain two-byte compression pointers so that each one points two bytes earlier than the previous, producing a chain length ofoffset / 2. For the 14-bit pointer field (max offset 16383) this gives up to ~8191 recursive frames. For a TCP DNS message the limit is the 16-bit length field (~32767 frames). Perl's default C stack handles only a few thousand frames; beyond that the process receives SIGSEGV or similar, which is a denial-of-service for any application parsing untrusted DNS data. The vulnerability is triggered byNet::DNS::Packet->new(\$wire)i.e. any point where the library decodes a DNS message from the network. - References
Affected packages
Debian:12 / libnet-dns-perl
Package
- Name
- libnet-dns-perl
- Purl
- pkg:deb/debian/libnet-dns-perl?arch=source&distro=bookworm
Debian:13 / libnet-dns-perl
Package
- Name
- libnet-dns-perl
- Purl
- pkg:deb/debian/libnet-dns-perl?arch=source&distro=trixie
Debian:14 / libnet-dns-perl
Package
- Name
- libnet-dns-perl
- Purl
- pkg:deb/debian/libnet-dns-perl?arch=source&distro=forky