CVE-2026-2703
xlnt-community xlnt Encrypted XLSX File base64.cpp decode_base64 off-by-one
Description
A weakness has been identified in xlnt-community xlnt up to 1.6.1. Impacted is the function xlnt::detail::decode_base64 of the file source/detail/cryptography/base64.cpp of the component Encrypted XLSX File Parser. Executing a manipulation can lead to off-by-one. The attack requires local access. The exploit has been made available to the public and could be used for attacks. This patch is called f2d7bf494e5c52706843cf7eb9892821bffb0734. Applying a patch is advised to resolve this issue.
INFO
Published Date :
Feb. 19, 2026, 7:17 a.m.
Last Modified :
March 10, 2026, 8:28 p.m.
Remotely Exploit :
No
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 2.0 | LOW | [email protected] | ||||
| CVSS 3.1 | LOW | [email protected] | ||||
| CVSS 3.1 | MEDIUM | [email protected] | ||||
| CVSS 4.0 | MEDIUM | [email protected] |
Solution
- Apply patch f2d7bf494e5c52706843cf7eb9892821bffb0734.
- Update the xlnt-community library to a patched version.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-2703.
| URL | Resource |
|---|---|
| https://github.com/oneafter/0128/blob/main/xl1/repro | Exploit |
| https://github.com/xlnt-community/xlnt/ | Product |
| https://github.com/xlnt-community/xlnt/commit/f2d7bf494e5c52706843cf7eb9892821bffb0734 | Patch |
| https://github.com/xlnt-community/xlnt/issues/137 | Exploit Issue Tracking Vendor Advisory |
| https://vuldb.com/?ctiid.346649 | Permissions Required VDB Entry |
| https://vuldb.com/?id.346649 | Third Party Advisory VDB Entry |
| https://vuldb.com/?submit.754377 | Third Party Advisory VDB Entry |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-2703 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-2703
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-2703 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-2703 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
Mar. 10, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Added CPE Configuration OR *cpe:2.3:a:xlnt-community:xlnt:*:*:*:*:*:*:*:* versions up to (including) 1.6.1 Added Reference Type VulDB: https://github.com/oneafter/0128/blob/main/xl1/repro Types: Exploit Added Reference Type VulDB: https://github.com/xlnt-community/xlnt/ Types: Product Added Reference Type VulDB: https://github.com/xlnt-community/xlnt/commit/f2d7bf494e5c52706843cf7eb9892821bffb0734 Types: Patch Added Reference Type VulDB: https://github.com/xlnt-community/xlnt/issues/137 Types: Exploit, Issue Tracking, Vendor Advisory Added Reference Type VulDB: https://vuldb.com/?ctiid.346649 Types: Permissions Required, VDB Entry Added Reference Type VulDB: https://vuldb.com/?id.346649 Types: Third Party Advisory, VDB Entry Added Reference Type VulDB: https://vuldb.com/?submit.754377 Types: Third Party Advisory, VDB Entry -
New CVE Received by [email protected]
Feb. 19, 2026
Action Type Old Value New Value Added Description A weakness has been identified in xlnt-community xlnt up to 1.6.1. Impacted is the function xlnt::detail::decode_base64 of the file source/detail/cryptography/base64.cpp of the component Encrypted XLSX File Parser. Executing a manipulation can lead to off-by-one. The attack requires local access. The exploit has been made available to the public and could be used for attacks. This patch is called f2d7bf494e5c52706843cf7eb9892821bffb0734. Applying a patch is advised to resolve this issue. Added CVSS V4.0 AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L Added CVSS V2 (AV:L/AC:L/Au:S/C:N/I:N/A:P) Added CWE CWE-189 Added CWE CWE-193 Added Reference https://github.com/oneafter/0128/blob/main/xl1/repro Added Reference https://github.com/xlnt-community/xlnt/ Added Reference https://github.com/xlnt-community/xlnt/commit/f2d7bf494e5c52706843cf7eb9892821bffb0734 Added Reference https://github.com/xlnt-community/xlnt/issues/137 Added Reference https://vuldb.com/?ctiid.346649 Added Reference https://vuldb.com/?id.346649 Added Reference https://vuldb.com/?submit.754377