xlnt-community xlnt up to 1.6.1 Compound Document Parser source/detail/binary.hpp append heap-based overflow

CVSS Meta Temp Score
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CTI Interest Score
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4.7$0-$5k0.00

Summaryinfo

A vulnerability classified as problematic was found in xlnt-community xlnt up to 1.6.1. The affected element is the function xlnt::detail::binary_writer::append of the file source/detail/binary.hpp of the component Compound Document Parser. Such manipulation leads to heap-based overflow. This vulnerability is referenced as CVE-2026-3463. The attack can only be performed from a local environment. Furthermore, an exploit is available. A patch should be applied to remediate this issue.

Detailsinfo

A vulnerability was found in xlnt-community xlnt up to 1.6.1 and classified as problematic. Affected by this issue is the function xlnt::detail::binary_writer::append of the file source/detail/binary.hpp of the component Compound Document Parser. The manipulation with an unknown input leads to a heap-based overflow vulnerability. Using CWE to declare the problem leads to CWE-122. A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc(). Impacted is availability.

The advisory is available at github.com. This vulnerability is handled as CVE-2026-3463. The exploitation is known to be easy. Local access is required to approach this attack. Technical details as well as a public exploit are known.

The exploit is available at github.com. It is declared as proof-of-concept.

Applying the patch 147 is able to eliminate this problem. The bugfix is ready for download at github.com.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Vendor

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 4.8
VulDB Meta Temp Score: 4.7

VulDB Base Score: 3.3
VulDB Temp Score: 3.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 7.8
NVD Vector: 🔒

CNA Base Score: 3.3
CNA Vector: 🔒

CVSSv2info

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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Heap-based overflow
CWE: CWE-122 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: No

Availability: 🔒
Access: Public
Status: Proof-of-Concept
Download: 🔒

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔒

Patch: 147

Timelineinfo

03/03/2026 Advisory disclosed
03/03/2026 +0 days VulDB entry created
03/11/2026 +8 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: 138
Status: Confirmed
Confirmation: 🔒

CVE: CVE-2026-3463 (🔒)
GCVE (CVE): GCVE-0-2026-3463
GCVE (VulDB): GCVE-100-348530
scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 03/03/2026 07:09
Updated: 03/11/2026 03:07
Changes: 03/03/2026 07:09 (61), 03/04/2026 19:48 (30), 03/11/2026 03:07 (12)
Complete: 🔍
Submitter: Oneafter
Cache ID: 216:F51:103

Submitinfo

Accepted

  • Submit #764643: xlnt-community xlnt commit bceb706 and before Heap-based Buffer Overflow (by Oneafter)

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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