{"cve":"CVE-2026-85644","nvd":{"published":"2026-09-28T17:17:51.127","modified":"2026-09-30T20:17:34.993","status":"Deferred","description":"XS::Parse::Infix versions from 0.40 through 0.49 for Perl treat a number as an array reference.\n\nThe 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.\n\nAn 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.\n\nAn 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.\n\nA simple proof-of-concept uses the zip operator:\n\n    use Syntax::Operator::Zip 'zip';\n\n    my @args = ([1], 2);\n    zip(@args);","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":["CWE-125","CWE-843"],"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","http://www.openwall.com/lists/oss-security/2026/09/28/14"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:56:48.555445741+00:00"},"epss":{"cve":"CVE-2026-85644","score":0.00373,"percentile":0.31044,"date":"2026-10-26"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}