Threats Tagged 'cve-2026-64194'

Net::DNS for Perl versions up to 1.55 contain a critical vulnerability (CVE-2026-64193) involving improper neutralization of directives in dynamically evaluated code, specifically in the handling of the EDNS EXTENDED-ERROR option. The vulnerability arises because the EXTRA-TEXT field is parsed and passed to Perl's eval with insufficient escaping, allowing remote attackers to execute arbitrary commands. This can lead to full system compromise without requiring authentication.

Libnet dns perl's Net::DNS versions through 1.55 for Perl contain a critical remote code execution vulnerability via EDNS EXTENDED ERROR (CVE-2026-64193) and a denial of service vulnerability caused by deep DNS compression pointer chains (CVE-2026-64194). These vulnerabilities have been fixed by the SUSE Product Security Team. Multiple specific versions are affected, but no explicit fixed versions are provided in the data.

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 < $offset` prevents forward and circular chains, but still allows arbitrarily long backward chains. The per-offset cache (`$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 of `offset / 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 by `Net::DNS::Packet->new(\$wire)` i.e. any point where the library decodes a DNS message from the network.