======================================================================== CVE-2026-85644 CPAN Security Group ========================================================================
CVE ID: CVE-2026-85644 Distribution: XS-Parse-Keyword Versions: from 0.40 through 0.49 MetaCPAN: https://metacpan.org/dist/XS-Parse-Keyword XS::Parse::Infix versions from 0.40 through 0.49 for Perl treat a number as an array reference Description ----------- XS::Parse::Infix versions from 0.40 through 0.49 for Perl treat a number as an array reference. The wrapper function XS::Parse::Infix generates for a list-associative infix operator checks whether arguments are array references, but it tests using SvRV() rather than SvROK(). SvRV() reads a union slot that only holds a referent once SvROK(sv) is true, so the guard never validates that it is a reference. For an IV or NV that slot holds the number itself, SvRV() returns the caller's value and SvTYPE() dereferences it at offset 12. This will generally result in a segmentation fault. An application that hands the wrapper a list built from decoded input (for example, from JSON) lets whoever supplies a number in that list choose the address that the interpreter dereferences. An ordinary string's byte 12 is rarely SVt_PVAV so the guard croaks by luck, but an attacker-crafted string carrying 0x0b there passes, and the buffer is then used as an AV head, with AvARRAY taken from bytes 16-23 and its entries pushed onto the Perl stack as live SVs. A simple proof-of-concept uses the zip operator: use Syntax::Operator::Zip 'zip'; my @args = ([1], 2); zip(@args); Problem types ------------- - CWE-843 Access of Resource Using Incompatible Type ('Type Confusion') - CWE-125 Out-of-bounds Read Workarounds ----------- For deployments that cannot upgrade, ensure that correct arguments (only array references where they are expected) are passed to list-associative operators that are defined with XS::Parse::Infix, such as those in Syntax::Operator::Zip. Solutions --------- Upgrade to XS-Parse-Keyword 0.50 or later. References ---------- https://metacpan.org/release/PEVANS/XS-Parse-Keyword-0.50/changes https://metacpan.org/release/PEVANS/XS-Parse-Keyword-0.50/diff/PEVANS/XS-Parse-Keyword-0.49#src/infix.c
