CVE-2026-59142
Out-of-bounds read in Data::HashMap::Shared (Perl) via untrusted mmap offsets.
Is CVE-2026-59142 being exploited?
Not confirmed. CVE-2026-59142 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.54% probability of exploitation in the next 30 days.
How severe is CVE-2026-59142?
CVE-2026-59142 is rated Critical with a CVSS score of 9.1. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-59142?
Yes. A fix has been recorded for CVE-2026-59142. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-59142 affect?
CVE-2026-59142 affects Perl Data::HashMap::Shared (< 0.14), Perl applications using shared mmap-backed hash maps. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-59142?
Upgrade to Data::HashMap::Shared v0.14+ and restrict backing-file write access
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Local actor who can modify the backing file can trigger OOB reads for memory disclosure or crash the process (DoS).
Immediate action required
- affected< 0.14
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.