CVE-2026-45380
bit7z: Path Traversal via Null Byte Injection from `gcount()` Off-by-One in `restoreSymlink()`
Description
bit7z is a cross-platform C++ static library that allows the compression/extraction of archive files. Prior to version 4.0.12, a one-byte off-by-one error in SafeOutPathBuilder::restoreSymlink() allows an attacker to craft a .7z archive that, when extracted with bit7z on any non-Windows platform, creates a symlink escaping the intended output directory. Subsequent archive entries extracted through this symlink write arbitrary files outside the extraction directory with the permissions of the extracting process. This issue has been patched in version 4.0.12.
INFO
Published Date :
June 10, 2026, 10:16 p.m.
Last Modified :
July 23, 2026, 9:10 a.m.
Remotely Exploit :
No
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | LOW | [email protected] | ||||
| CVSS 3.1 | LOW | MITRE-CVE |
Solution
- Update bit7z to version 4.0.12 or later.
- Re-extract archives using the updated library.
Public PoC/Exploit Available at Github
CVE-2026-45380 has a 1 public
PoC/Exploit available at Github.
Go to the Public Exploits tab to see the list.
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-2026-45380.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-45380 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-2026-45380
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).
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The following list is the news that have been mention
CVE-2026-45380 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-45380 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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CVE Translated by [email protected]
Jul. 23, 2026
Action Type Old Value New Value Added Translation Title: bit7z de rikyoz, Description: bit7z es una biblioteca estática de C++ multiplataforma que permite la compresión/extracción de archivos de archivo. Antes de la versión 4.0.12, un error de un byte por uno en SafeOutPathBuilder::restoreSymlink() permite a un atacante crear un archivo .7z que, al ser extraído con bit7z en cualquier plataforma que no sea Windows, crea un enlace simbólico que escapa del directorio de salida previsto. Las entradas de archivo subsiguientes extraídas a través de este enlace simbólico escriben archivos arbitrarios fuera del directorio de extracción con los permisos del proceso de extracción. Este problema ha sido parcheado en la versión 4.0.12. -
CVE Modified by [email protected]
Jun. 17, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'rikyoz', 'product': 'bit7z', 'versions': [{'status': 'affected', 'version': '< 4.0.12'}]}] -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 17, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-45380', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'poc'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-06-11T14:12:55.595820Z'} -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 11, 2026
Action Type Old Value New Value Added Reference https://github.com/rikyoz/bit7z/security/advisories/GHSA-8wj8-9jwv-j24v -
New CVE Received by [email protected]
Jun. 10, 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 4.0.12, a one-byte off-by-one error in SafeOutPathBuilder::restoreSymlink() allows an attacker to craft a .7z archive that, when extracted with bit7z on any non-Windows platform, creates a symlink escaping the intended output directory. Subsequent archive entries extracted through this symlink write arbitrary files outside the extraction directory with the permissions of the extracting process. This issue has been patched in version 4.0.12. Added CVSS V3.1 AV:L/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:L Added CWE CWE-22 Added CWE CWE-193 Added Reference https://github.com/rikyoz/bit7z/releases/tag/v4.0.12 Added Reference https://github.com/rikyoz/bit7z/security/advisories/GHSA-8wj8-9jwv-j24v