CVE-2026-59140: 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

Severity: critical (CVSS 9.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-07-21 · updated 2026-10-24
Weakness: CWE-125

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.

Affected products

EGOR Data::SortedSet::Shared: before 0.03 — fixed in 0.03

How to fix

Upgrade to a fixed version: EGOR Data::SortedSet::Shared 0.03. Check the vendor advisory for mitigations.

References

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