Is CVE-2026-110598 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-110598 being exploited in the wild.

How severe is CVE-2026-110598?

Medium severity, with a CVSS score of 6.1, published 14 October 2026.

Which products and versions are affected?

Libyal Libpff through 20260926.

Is there a fix for CVE-2026-110598?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2026-110598 attacked?

It is attacked with local access, in a software library.

Am I affected by CVE-2026-110598?

Check whether you run Libyal Libpff at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-110598: libyal libpff integer underflow in record entry parsing

CVE-2026-110598 · Severity: medium · CVSS 6.1 · Published 2026-10-14

libpff is a library for reading Outlook PST, OST, and PAB email files. An integer underflow flaw in the multi-value record parsing allows attackers to craft malicious files that trigger out-of-bounds heap reads, potentially crashing the application or exposing sensitive data from adjacent memory.

Technologies: Libyal Libpff. Vendors: Libyal.

Quick answers

Is CVE-2026-110598 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-110598 being exploited in the wild.
How severe is CVE-2026-110598?: Medium severity, with a CVSS score of 6.1, published 14 October 2026.
Which products and versions are affected?: Libyal Libpff through 20260926.
Is there a fix for CVE-2026-110598?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-110598 attacked?: It is attacked with local access, in a software library.
Am I affected by CVE-2026-110598?: Check whether you run Libyal Libpff at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

An integer underflow in libpff_record_entry_get_multi_value() occurs when processing multi-value property offsets (PT_MV_STRING8, PT_MV_UNICODE, or PT_MV_BINARY types) in crafted PST/OST/PAB files. Attackers can create files with non-monotonic (decreasing) offsets to trigger out-of-bounds reads on the heap. The vulnerability requires opening a malicious file and does not require authentication or network access.

Affected products

libyal libpff through 20260926

Timeline

2026-10-14: disclosed

References

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