What is the CVSS score of CVE-2026-59140?

CVE-2026-59140 has a CVSS 3.1 base score of 9.1 (Critical). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H. EPSS exploitation probability: 0.2%.

How to fix or mitigate CVE-2026-59140?

Within 24 hours, enumerate all production and development systems running Perl Data::SortedSet::Shared and identify installed versions, prioritizing applications handling sensitive or customer-facing data. Within 7 days, update the module to version 0.03 or later across development and staging environments, then execute functional test suites to verify inter-process communication and data consistency remain unaffected. Within 30 days, deploy version 0.03 or later to all production systems in a controlled manner, validate successful application operation, and monitor for anomalies over 72 hours post-deployment.

CVE-2026-59140

EUVD-2026-46353 CRITICAL

Out-of-bounds Read (CWE-125)

2026-07-21 9b29abf9-4ab0-4765-b253-1875cd9b441e

GHSA-6qfv-wgp3-38c4

Buffer Overflow Information Disclosure

9.1

CVSS 3.1 · Vendor: 9b29abf9-4ab0-4765-b253-1875cd9b441e

Severity by source

Vendor (9b29abf9-4ab0-4765-b253-1875cd9b441e) PRIMARY

9.1 CRITICAL

AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

Primary rating from Vendor (9b29abf9-4ab0-4765-b253-1875cd9b441e) · only source for this CVE.

CVSS VectorVendor: 9b29abf9-4ab0-4765-b253-1875cd9b441e

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

None

Availability

High

Lifecycle Timeline

Analysis Generated

Jul 22, 2026 - 21:09 vuln.today

CVSS changed

Jul 22, 2026 - 20:22 NVD

9.1 (CRITICAL)

Patch available

Jul 21, 2026 - 20:18 EUVD

CVE Published

Jul 21, 2026 - 19:17 cve.org

UNKNOWN (no severity yet)

CVE Published

Jul 21, 2026 - 19:17 cve.org

CRITICAL 9.1

DescriptionCVE.org

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.

AnalysisAI

Out-of-bounds memory read in the Perl module Data::SortedSet::Shared before 0.03 lets a local peer who can write the shared mmap-backed file poison tree link indices, causing the next rank, min, or max query to dereference an out-of-bounds node and leak adjacent process memory or crash. The flaw stems from an attach-time validator that checks only the root index, deferring the full structural check to a separate, rarely-invoked validate method. No public exploit has been identified at time of analysis, EPSS risk is low (0.16%, 5th percentile), and it is not on the CISA KEV list.