title: Sandbox escape via various forms of "format" in RestrictedPython
description: 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.
problem types: CWE-74: Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')
affected:
{
vendor: zopefoundation
product: RestrictedPython
versions:
version: < 5.4, status: affected
version: >= 6.0, < 6.1, status: affected
}
metrics:
cvssV3_1: [
attackComplexity: LOW
attackVector: NETWORK
availabilityImpact: LOW
baseScore: 8.3
baseSeverity: HIGH
confidentialityImpact: HIGH
integrityImpact: HIGH
privilegesRequired: HIGH
scope: CHANGED
userInteraction: REQUIRED
vectorString: CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:H/I:H/A:L
version: 3.1
]