CVE-2026-65064
Received
Received - Intake
Insecure File Creation in Data::HashMap::Shared Perl Module
Vulnerability report for CVE-2026-65064, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-07-21
Last updated on: 2026-07-21
Assigner: CPANSec
Description
Description
Data::HashMap::Shared versions before 0.14 for Perl create a world-readable mmap backing file and open it without O_EXCL or O_NOFOLLOW.
The segment is created in shm_generic.h with open(path, O_RDWR | O_CREAT | O_CLOEXEC, 0666). The mode is 0666, so under the default umask 022 the file is created mode 0644 (world-readable). O_NOFOLLOW is absent, so a symlink planted at the path is followed, and O_EXCL is absent, so the open silently uses a pre-planted file instead of failing.
A "Shared" segment naturally lives in a shared directory such as /tmp or /dev/shm, where any local user can read the IPC payloads stored in the world-readable segment, and a pre-planted file or symlink at the path lets a local attacker win a pre-creation race or redirect the open.
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
Currently, no data is known.
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-732 | The product specifies permissions for a security-critical resource in a way that allows that resource to be read or modified by unintended actors. |
| CWE-59 | The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource. |
