Vulnerability record · CVE-2026-59140 · published 21 July 2026
CVE-2026-59140: Out-of-bounds read vulnerability
Data::SortedSet::Shared versions before 0.03 for Perl allow an out-of-bounds read via unvalidated node indices in the rank and min/max query paths. The attach-time validator ss_validate_header bounds only the root index against the node pool (node_capacity). The order-statistics and min/max queries then follow children[], leftmost and rightmost node indices read raw from the mmap'd segment without bounding them against node_capacity. A full structural check (ss_validate_tree) exists but runs only via an explicit validate method, not on attach. A local peer that can write the backing file can leave the header valid while poisoning the tree links, so the next rank, min or max query dereferences an out-of-bounds node index, reading adjacent memory or crashing the process.
Description
Data::SortedSet::Shared versions before 0.03 for Perl allow an out-of-bounds read via unvalidated node indices in the rank and min/max query paths. The attach-time validator ss_validate_header bounds only the root index against the node pool (node_capacity). The order-statistics and min/max queries then follow children[], leftmost and rightmost node indices read raw from the mmap'd segment without bounding them against node_capacity. A full structural check (ss_validate_tree) exists but runs only via an explicit validate method, not on attach. A local peer that can write the backing file can leave the header valid while poisoning the tree links, so the next rank, min or max query dereferences an out-of-bounds node index, reading adjacent memory or crashing the process.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
References
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Related vulnerabilities
Same products first, then exploited flaws of the same weakness class.
Source: NIST National Vulnerability Database (record CVE-2026-59140), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.