https://cve.radiocsirt.org/rss/recent/all/10 Most recent entries from all 2026-10-02T21:34:38.920825+00:00 Vulnerability-Lookup csirt@opendfir.org python-feedgen Contains only the most 10 recent entries. https://cve.radiocsirt.org/vuln/cve-2023-41039 CVE-2023-41039 — Sandbox escape via various forms of "format" in RestrictedPython 2026-10-02T21:34:38.924365+00:00

Affected: zopefoundation RestrictedPython

RestrictedPython is a restricted execution environment for Python to run untrusted code. Python's "format" functionality allows someone controlling the format string to "read" all objects accessible through recursive attribute lookup and subscription from objects he can access. This can lead to critical information disclosure. With `RestrictedPython`, the format functionality is available via the `format` and `format_map` methods of `str` (and `unicode`) (accessed either via the class or its instances) and via `string.Formatter`. All known versions of `RestrictedPython` are vulnerable. This issue has been addressed in commit `4134aedcff1` which has been included in the 5.4 and 6.2 releases. Users are advised to upgrade. There are no known workarounds for this vulnerability.

 https://cve.radiocsirt.org/vuln/ghsa-xjw2-6jm9-rf67 GHSA-xjw2-6jm9-rf67 — Sandbox escape via various forms of "format". 2026-10-02T21:34:38.924423+00:00

Affected: PyPI: RestrictedPython

### Impact Python's "format" functionality allows someone controlling the format string to "read" all objects accessible through recursive attribute lookup and subscription from objects he can access. This can lead to critical information disclosure. With `RestrictedPython`, the format functionality is available via the `format` and `format_map` methods of `str` (and `unicode`) (accessed either via the class or its instances) and via `string.Formatter`. All known versions of `RestrictedPython` are vulnerable.

### Patches The issue will be fixed in 5.4 and 6.2.

### Workarounds There are no workarounds to fix the issue without upgrading.

### References * https://docs.python.org/3/library/stdtypes.html#str.format_map * http://lucumr.pocoo.org/2016/12/29/careful-with-str-format/ * https://www.exploit-db.com/exploits/51580

### For more information

If you have any questions or comments about this advisory:

* Open an issue in the [RestrictedPython issue tracker](https://github.com/zopefoundation/RestrictedPython/issues) * Email us at [security@plone.org](mailto:security@plone.org)

### Credits

Thanks for analysing and reporting the go to:

* Abhishek Govindarasu * Ankush Menat * Ward Theunisse