CVE-2026-27117
bit7z has a path traversal vulnerability
Description
bit7z is a cross-platform C++ static library that allows the compression/extraction of archive files. Prior to version 4.0.11, a path traversal vulnerability ("Zip Slip") exists in bit7z's archive extraction functionality. The library does not adequately validate file paths contained in archive entries, allowing files to be written outside the intended extraction directory through three distinct mechanisms: relative path traversal, absolute path traversal, and symbolic link traversal. An attacker can exploit this by providing a malicious archive to any application that uses bit7z to extract untrusted archives. Successful exploitation results in arbitrary file write with the privileges of the process performing the extraction. This could lead to overwriting of application binaries, configuration files, or other sensitive data. The vulnerability does not directly enable reading of file contents; the confidentiality impact is limited to the calling application's own behavior after extraction. However, applications that subsequently serve or display extracted files may face secondary confidentiality risks from attacker-created symlinks. Fixes have been released in version 4.0.11. If upgrading is not immediately possible, users can mitigate the vulnerability by validating each entry's destination path before writing. Other mitigations include running extraction with least privilege and extracting untrusted archives in a sandboxed directory.
INFO
Published Date :
Feb. 24, 2026, 10:16 p.m.
Last Modified :
Feb. 25, 2026, 8:29 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | [email protected] | ||||
| CVSS 3.1 | MEDIUM | MITRE-CVE | ||||
| CVSS 3.1 | HIGH | [email protected] |
Solution
- Update bit7z to version 4.0.11 or later.
- Validate extracted file paths before writing.
- Run extraction with least privilege.
- Extract archives in a sandboxed directory.
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-2026-27117.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-27117 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-2026-27117
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-2026-27117 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-27117 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.
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Initial Analysis by [email protected]
Feb. 25, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N Added CWE CWE-22 Added CPE Configuration OR *cpe:2.3:a:rikyoz:bit7z:*:*:*:*:*:*:*:* versions up to (excluding) 4.0.11 Added Reference Type GitHub, Inc.: https://github.com/rikyoz/bit7z/commit/31763da9a3e41a199c141c8d71f6c11de24b45cf Types: Patch Added Reference Type GitHub, Inc.: https://github.com/rikyoz/bit7z/commit/9e020483eefa5825ec9310b1d869933d4f77f969 Types: Patch Added Reference Type GitHub, Inc.: https://github.com/rikyoz/bit7z/releases/tag/v4.0.11 Types: Release Notes Added Reference Type GitHub, Inc.: https://github.com/rikyoz/bit7z/security/advisories/GHSA-qvjh-hhw4-3gx9 Types: Exploit, Vendor Advisory -
New CVE Received by [email protected]
Feb. 24, 2026
Action Type Old Value New Value Added Description bit7z is a cross-platform C++ static library that allows the compression/extraction of archive files. Prior to version 4.0.11, a path traversal vulnerability ("Zip Slip") exists in bit7z's archive extraction functionality. The library does not adequately validate file paths contained in archive entries, allowing files to be written outside the intended extraction directory through three distinct mechanisms: relative path traversal, absolute path traversal, and symbolic link traversal. An attacker can exploit this by providing a malicious archive to any application that uses bit7z to extract untrusted archives. Successful exploitation results in arbitrary file write with the privileges of the process performing the extraction. This could lead to overwriting of application binaries, configuration files, or other sensitive data. The vulnerability does not directly enable reading of file contents; the confidentiality impact is limited to the calling application's own behavior after extraction. However, applications that subsequently serve or display extracted files may face secondary confidentiality risks from attacker-created symlinks. Fixes have been released in version 4.0.11. If upgrading is not immediately possible, users can mitigate the vulnerability by validating each entry's destination path before writing. Other mitigations include running extraction with least privilege and extracting untrusted archives in a sandboxed directory. Added CVSS V3.1 AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N Added CWE CWE-22 Added CWE CWE-23 Added CWE CWE-36 Added Reference https://github.com/rikyoz/bit7z/commit/31763da9a3e41a199c141c8d71f6c11de24b45cf Added Reference https://github.com/rikyoz/bit7z/commit/9e020483eefa5825ec9310b1d869933d4f77f969 Added Reference https://github.com/rikyoz/bit7z/releases/tag/v4.0.11 Added Reference https://github.com/rikyoz/bit7z/security/advisories/GHSA-qvjh-hhw4-3gx9