CVE-2026-65066
Severity CVSS v4.0:
Pending analysis
Type:
CWE-59
Link Following
Publication date:
21/07/2026
Last modified:
23/07/2026
Description
Data::RingBuffer::Shared versions before 0.04 for Perl create a world-readable mmap backing file and open it without O_EXCL or O_NOFOLLOW.<br />
<br />
The segment is created in ring.h with open(path, O_RDWR|O_CREAT, 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.<br />
<br />
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.
Impact
Base Score 3.x
3.80
Severity 3.x
LOW