EGOR Data::HashMap::Shared up to 0.13 shm_generic.h open path toctou

Summaryinfo

A vulnerability was found in EGOR Data::HashMap::Shared up to 0.13. It has been classified as problematic. This vulnerability affects the function Open of the file shm_generic.h of the component Shared. This manipulation of the argument path causes toctou. This vulnerability appears as CVE-2026-65064. The attack requires local access. There is no available exploit.

Detailsinfo

A vulnerability classified as problematic was found in EGOR Data::HashMap::Shared up to 0.13. Affected by this vulnerability is the function open of the file shm_generic.h of the component Shared. The manipulation of the argument path with an unknown input leads to a toctou vulnerability. The CWE definition for the vulnerability is CWE-367. The product checks the state of a resource before using that resource, but the resource's state can change between the check and the use in a way that invalidates the results of the check. This can cause the product to perform invalid actions when the resource is in an unexpected state. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

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.

It is possible to read the advisory at metacpan.org. This vulnerability is known as CVE-2026-65064 since 07/21/2026. The exploitation appears to be easy. Attacking locally is a requirement. Technical details of the vulnerability are known, but there is no available exploit.

Upgrading to version 0.14 eliminates this vulnerability.

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Productinfo

Vendor

• EGOR

Name

• Data::HashMap::Shared

Version

• 0.1
• 0.2
• 0.3
• 0.4
• 0.5
• 0.6
• 0.7
• 0.8
• 0.9
• 0.10
• 0.11
• 0.12
• 0.13

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

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