CVE-2026-114608

Impact

Since 2006 / pylint 0.15.2, pylint caches its stats as pickles in PYLINT_HOME and reload them on the next run with pickle.load. Someone without access to the configuration or linted code, but with access to the cache directory (predictable PYLINT_HOME on a multi-user host) can write a crafted pickle that will runs arbitrary code when pylint access its stat cache.

Patches

From pylint 4.0.9, the result cache is now stored as JSON instead of pickle, preventing code-execution.

Workarounds

Until upgrading do not point PYLINT_HOME to an untrusted, shared, or group-writable directory. The default value, ~/.cache/pylint, is writable only by the user running pylint.

Credits

• Reported privately via Tidelift coordinated disclosure (Dan Lenz).

Pylint is a Python source code analyzer which looks for programming errors, helps enforcing a coding standard and sniffs for some code smells (as defined in Martin Fowler's Refactoring book). Pylint can be seen as another PyChecker since nearly all tests you can do with PyChecker can also be done with Pylint. However, Pylint offers some more features, like checking length of lines of code, checking if variable names are well-formed according to your coding standard, or checking if declared interfaces are truly implemented, and much more. Additionally, it is possible to write plugins to add your own checks.

Security Fix(es):

Pylint is a static code analyser for Python. From 0.15.2 until 4.0.9, Pylint stores module statistics in predictable files under PYLINT_HOME and loads those files with pickle.load on a later run. An attacker who can write to a shared, group-writable, or otherwise untrusted cache directory can replace a stats cache with crafted serialized data, causing arbitrary code to execute with the privileges of the user who next runs Pylint. The default per-user cache is not normally writable by another user. This issue is fixed in version 4.0.9.(CVE-2026-114608)

Pylint is a Python source code analyzer which looks for programming errors, helps enforcing a coding standard and sniffs for some code smells (as defined in Martin Fowler's Refactoring book). Pylint can be seen as another PyChecker since nearly all tests you can do with PyChecker can also be done with Pylint. However, Pylint offers some more features, like checking length of lines of code, checking if variable names are well-formed according to your coding standard, or checking if declared interfaces are truly implemented, and much more. Additionally, it is possible to write plugins to add your own checks.

Security Fix(es):

Pylint is a static code analyser for Python. From 0.15.2 until 4.0.9, Pylint stores module statistics in predictable files under PYLINT_HOME and loads those files with pickle.load on a later run. An attacker who can write to a shared, group-writable, or otherwise untrusted cache directory can replace a stats cache with crafted serialized data, causing arbitrary code to execute with the privileges of the user who next runs Pylint. The default per-user cache is not normally writable by another user. This issue is fixed in version 4.0.9.(CVE-2026-114608)

Pylint is a Python source code analyzer which looks for programming errors, helps enforcing a coding standard and sniffs for some code smells (as defined in Martin Fowler's Refactoring book). Pylint can be seen as another PyChecker since nearly all tests you can do with PyChecker can also be done with Pylint. However, Pylint offers some more features, like checking length of lines of code, checking if variable names are well-formed according to your coding standard, or checking if declared interfaces are truly implemented, and much more. Additionally, it is possible to write plugins to add your own checks.

Security Fix(es):

Pylint is a static code analyser for Python. From 0.15.2 until 4.0.9, Pylint stores module statistics in predictable files under PYLINT_HOME and loads those files with pickle.load on a later run. An attacker who can write to a shared, group-writable, or otherwise untrusted cache directory can replace a stats cache with crafted serialized data, causing arbitrary code to execute with the privileges of the user who next runs Pylint. The default per-user cache is not normally writable by another user. This issue is fixed in version 4.0.9.(CVE-2026-114608)

Pylint is a Python source code analyzer which looks for programming errors, helps enforcing a coding standard and sniffs for some code smells (as defined in Martin Fowler's Refactoring book). Pylint can be seen as another PyChecker since nearly all tests you can do with PyChecker can also be done with Pylint. However, Pylint offers some more features, like checking length of lines of code, checking if variable names are well-formed according to your coding standard, or checking if declared interfaces are truly implemented, and much more. Additionally, it is possible to write plugins to add your own checks.

Security Fix(es):

Pylint is a static code analyser for Python. From 0.15.2 until 4.0.9, Pylint stores module statistics in predictable files under PYLINT_HOME and loads those files with pickle.load on a later run. An attacker who can write to a shared, group-writable, or otherwise untrusted cache directory can replace a stats cache with crafted serialized data, causing arbitrary code to execute with the privileges of the user who next runs Pylint. The default per-user cache is not normally writable by another user. This issue is fixed in version 4.0.9.(CVE-2026-114608)

Pylint is a static code analyser for Python. From 0.15.2 until 4.0.9, Pylint stores module statistics in predictable files under PYLINT_HOME and loads those files with pickle.load on a later run. An attacker who can write to a shared, group-writable, or otherwise untrusted cache directory can replace a stats cache with crafted serialized data, causing arbitrary code to execute with the privileges of the user who next runs Pylint. The default per-user cache is not normally writable by another user. This issue is fixed in version 4.0.9.

Pylint is a static code analyser for Python. From 0.15.2 until 4.0.9, Pylint stores module statistics in predictable files under PYLINT_HOME and loads those files with pickle.load on a later run. An attacker who can write to a shared, group-writable, or otherwise untrusted cache directory can replace a stats cache with crafted serialized data, causing arbitrary code to execute with the privileges of the user who next runs Pylint. The default per-user cache is not normally writable by another user. This issue is fixed in version 4.0.9.

These are all security issues fixed in the python313-pylint-4.1.3-1.1 package on the GA media of openSUSE Tumbleweed.