What is CVE-2026-3463?

CVE-2026-3463 is a low-severity vulnerability in Xlnt-Community Xlnt, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 3.3/10. Published 2026-03-03.

How severe is CVE-2026-3463?

Low severity. CVSS v3 base score is 3.3 out of 10.

Buffer overflow in Xlnt-Community Xlnt

CVE-2026-3463

A weakness has been identified in xlnt-community xlnt up to 1.6.1. Impacted is the function xlnt::detail::binary_writer::append of the file source/detail/binary.hpp of the component Compound Document Parser. This manipulation causes heap-based buffer overflow. The attack can only be executed locally. The exploit has been made available to the public and could be used for attacks. Patch name: 147. It is suggested to install a patch to address this issue.

Vulnerability class: Buffer Overflow

Published 2026-03-03 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 3.3 (Low). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L.

EPSS exploit prediction

EPSS: 0.002 (12.3th percentile), scored 2026-10-01.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 12th percentile — 12.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: +0.000

Affected products

Xlnt-Community Xlnt — versions 1.6.0, 1.6.1

Weakness classification (CWE)

References

vuldb.com/ (technical-description, VDB Entry, Third Party Advisory, vdb-entry)
vuldb.com/ (signature, Permissions Required, permissions-required, VDB Entry)
vuldb.com/ (VDB Entry, Third Party Advisory, third-party-advisory)
github.com/xlnt-community/xlnt/issues/138 (issue-tracking, Exploit, Issue Tracking, Vendor Advisory)
github.com/xlnt-community/xlnt/issues/138 (issue-tracking, Issue Tracking)
github.com/oneafter/0128/blob/main/xl2/repro (Exploit, exploit)
github.com/xlnt-community/xlnt/pull/147 (issue-tracking, patch, Issue Tracking)
github.com/xlnt-community/xlnt/ (Product, product)

Frequently asked questions

What is CVE-2026-3463?: CVE-2026-3463 is a low-severity vulnerability in Xlnt-Community Xlnt, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 3.3/10. Published 2026-03-03.
How severe is CVE-2026-3463?: Low severity. CVSS v3 base score is 3.3 out of 10.