https://vulnerability.circl.lu Contains only the most 10 recent entries. http://www.rssboard.org/rss-specification python-feedgen en Mon, 28 Sep 2026 13:33:22 +0000 https://vulnerability.circl.lu/vuln/cve-2026-22701 <p><strong>Affected:</strong> tox-dev filelock</p> <p>filelock is a platform-independent file lock for Python. Prior to version 3.20.3, a TOCTOU race condition vulnerability exists in the SoftFileLock implementation of the filelock package. An attacker with local filesystem access and permission to create symlinks can exploit a race condition between the permission validation and file creation to cause lock operations to fail or behave unexpectedly. The vulnerability occurs in the _acquire() method between raise_on_not_writable_file() (permission check) and os.open() (file creation). During this race window, an attacker can create a symlink at the lock file path, potentially causing the lock to operate on an unintended target file or leading to denial of service. This issue has been patched in version 3.20.3.</p> <p><strong>Affected:</strong> tox-dev filelock</p> <p>filelock is a platform-independent file lock for Python. Prior to version 3.20.3, a TOCTOU race condition vulnerability exists in the SoftFileLock implementation of the filelock package. An attacker with local filesystem access and permission to create symlinks can exploit a race condition between the permission validation and file creation to cause lock operations to fail or behave unexpectedly. The vulnerability occurs in the _acquire() method between raise_on_not_writable_file() (permission check) and os.open() (file creation). During this race window, an attacker can create a symlink at the lock file path, potentially causing the lock to operate on an unintended target file or leading to denial of service. This issue has been patched in version 3.20.3.</p> https://vulnerability.circl.lu/vuln/cve-2026-22701 https://vulnerability.circl.lu/vuln/ghsa-qmgc-5h2g-mvrw <p><strong>Affected:</strong> PyPI: filelock</p> <p>## Vulnerability Summary</p> <p>**Title:** Time-of-Check-Time-of-Use (TOCTOU) Symlink Vulnerability in SoftFileLock</p> <p>**Affected Component:** `filelock` package - `SoftFileLock` class **File:** `src/filelock/_soft.py` lines 17-27 **CWE:** CWE-362, CWE-367, CWE-59</p> <p>---</p> <p>## Description</p> <p>A TOCTOU race condition vulnerability exists in the `SoftFileLock` implementation of the filelock package. An attacker with local filesystem access and permission to create symlinks can exploit a race condition between the permission validation and file creation to cause lock operations to fail or behave unexpectedly.</p> <p>The vulnerability occurs in the `_acquire()` method between `raise_on_not_writable_file()` (permission check) and `os.open()` (file creation). During this race window, an attacker can create a symlink at the lock file path, potentially causing the lock to operate on an unintended target file or leading to denial of service.</p> <p>### Attack Scenario</p> <p>``` 1. Lock attempts to acquire on /tmp/app.lock 2. Permission validation passes 3. [RACE WINDOW] - Attacker creates: ln -s /tmp/important.txt /tmp/app.lock 4. os.open() tries to create lock file 5. Lock operates on attacker-controlled target file or fails ```</p> <p>---</p> <p>## Impact</p> <p>_What kind of vulnerability is it? Who is impacted?_</p> <p>This is a **Time-of-Check-Time-of-Use (TOCTOU) race condition vulnerability** affecting any application using `SoftFileLock` for inter-process synchronization.</p> <p>**Affected Users:** - Applications using `filelock.SoftFil…</p> <p><strong>Affected:</strong> PyPI: filelock</p> <p>## Vulnerability Summary</p> <p>**Title:** Time-of-Check-Time-of-Use (TOCTOU) Symlink Vulnerability in SoftFileLock</p> <p>**Affected Component:** `filelock` package - `SoftFileLock` class **File:** `src/filelock/_soft.py` lines 17-27 **CWE:** CWE-362, CWE-367, CWE-59</p> <p>---</p> <p>## Description</p> <p>A TOCTOU race condition vulnerability exists in the `SoftFileLock` implementation of the filelock package. An attacker with local filesystem access and permission to create symlinks can exploit a race condition between the permission validation and file creation to cause lock operations to fail or behave unexpectedly.</p> <p>The vulnerability occurs in the `_acquire()` method between `raise_on_not_writable_file()` (permission check) and `os.open()` (file creation). During this race window, an attacker can create a symlink at the lock file path, potentially causing the lock to operate on an unintended target file or leading to denial of service.</p> <p>### Attack Scenario</p> <p>``` 1. Lock attempts to acquire on /tmp/app.lock 2. Permission validation passes 3. [RACE WINDOW] - Attacker creates: ln -s /tmp/important.txt /tmp/app.lock 4. os.open() tries to create lock file 5. Lock operates on attacker-controlled target file or fails ```</p> <p>---</p> <p>## Impact</p> <p>_What kind of vulnerability is it? Who is impacted?_</p> <p>This is a **Time-of-Check-Time-of-Use (TOCTOU) race condition vulnerability** affecting any application using `SoftFileLock` for inter-process synchronization.</p> <p>**Affected Users:** - Applications using `filelock.SoftFil…</p> https://vulnerability.circl.lu/vuln/ghsa-qmgc-5h2g-mvrw https://vulnerability.circl.lu/vuln/pysec-2026-1374 <p><strong>Affected:</strong> PyPI: filelock</p> <p>## Vulnerability Summary</p> <p>**Title:** Time-of-Check-Time-of-Use (TOCTOU) Symlink Vulnerability in SoftFileLock</p> <p>**Affected Component:** `filelock` package - `SoftFileLock` class **File:** `src/filelock/_soft.py` lines 17-27 **CWE:** CWE-362, CWE-367, CWE-59</p> <p>---</p> <p>## Description</p> <p>A TOCTOU race condition vulnerability exists in the `SoftFileLock` implementation of the filelock package. An attacker with local filesystem access and permission to create symlinks can exploit a race condition between the permission validation and file creation to cause lock operations to fail or behave unexpectedly.</p> <p>The vulnerability occurs in the `_acquire()` method between `raise_on_not_writable_file()` (permission check) and `os.open()` (file creation). During this race window, an attacker can create a symlink at the lock file path, potentially causing the lock to operate on an unintended target file or leading to denial of service.</p> <p>### Attack Scenario</p> <p>``` 1. Lock attempts to acquire on /tmp/app.lock 2. Permission validation passes 3. [RACE WINDOW] - Attacker creates: ln -s /tmp/important.txt /tmp/app.lock 4. os.open() tries to create lock file 5. Lock operates on attacker-controlled target file or fails ```</p> <p>---</p> <p>## Impact</p> <p>_What kind of vulnerability is it? Who is impacted?_</p> <p>This is a **Time-of-Check-Time-of-Use (TOCTOU) race condition vulnerability** affecting any application using `SoftFileLock` for inter-process synchronization.</p> <p>**Affected Users:** - Applications using `filelock.SoftFil…</p> <p><strong>Affected:</strong> PyPI: filelock</p> <p>## Vulnerability Summary</p> <p>**Title:** Time-of-Check-Time-of-Use (TOCTOU) Symlink Vulnerability in SoftFileLock</p> <p>**Affected Component:** `filelock` package - `SoftFileLock` class **File:** `src/filelock/_soft.py` lines 17-27 **CWE:** CWE-362, CWE-367, CWE-59</p> <p>---</p> <p>## Description</p> <p>A TOCTOU race condition vulnerability exists in the `SoftFileLock` implementation of the filelock package. An attacker with local filesystem access and permission to create symlinks can exploit a race condition between the permission validation and file creation to cause lock operations to fail or behave unexpectedly.</p> <p>The vulnerability occurs in the `_acquire()` method between `raise_on_not_writable_file()` (permission check) and `os.open()` (file creation). During this race window, an attacker can create a symlink at the lock file path, potentially causing the lock to operate on an unintended target file or leading to denial of service.</p> <p>### Attack Scenario</p> <p>``` 1. Lock attempts to acquire on /tmp/app.lock 2. Permission validation passes 3. [RACE WINDOW] - Attacker creates: ln -s /tmp/important.txt /tmp/app.lock 4. os.open() tries to create lock file 5. Lock operates on attacker-controlled target file or fails ```</p> <p>---</p> <p>## Impact</p> <p>_What kind of vulnerability is it? Who is impacted?_</p> <p>This is a **Time-of-Check-Time-of-Use (TOCTOU) race condition vulnerability** affecting any application using `SoftFileLock` for inter-process synchronization.</p> <p>**Affected Users:** - Applications using `filelock.SoftFil…</p> https://vulnerability.circl.lu/vuln/pysec-2026-1374