zopefoundation RestrictedPython up to 8.2 Argument Validation check_function_argument_names Local access control

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.0$0-$5k0.56+

Summaryinfo

A vulnerability, which was classified as critical, was found in zopefoundation RestrictedPython up to 8.2. Affected by this vulnerability is the function check_function_argument_names of the component Argument Validation. Such manipulation of the argument Local leads to access control. This vulnerability is documented as CVE-2026-55830. The attack can be executed remotely. There is not any exploit available.

Detailsinfo

A vulnerability was found in zopefoundation RestrictedPython up to 8.2. It has been rated as critical. Affected by this issue is the function check_function_argument_names of the component Argument Validation. The manipulation of the argument local with an unknown input leads to a access control vulnerability. Using CWE to declare the problem leads to CWE-284. The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor. Impacted is confidentiality, integrity, and availability. CVE summarizes:

RestrictedPython is a tool that helps to define a subset of the Python language which allows to provide a program input into a trusted environment. Prior to 8.3, check_function_argument_names() rejected protected guard hook names for regular, variadic, and keyword-only arguments but omitted positional-only arguments, allowing __getattr__, _getitem_, _write_, or _print_ to be shadowed by a local parameter and bypass the embedding application's access policy. This issue is fixed in version 8.3.

The advisory is shared for download at github.com. This vulnerability is handled as CVE-2026-55830 since 06/17/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. Successful exploitation requires user interaction by the victim. There are known technical details, but no exploit is available. The MITRE ATT&CK project declares the attack technique as T1068.

Upgrading to version 8.3 eliminates this vulnerability.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

Vendor

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.0

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Access control
CWE: CWE-284 / CWE-266
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Upgrade: RestrictedPython 8.3

Timelineinfo

06/17/2026 CVE reserved
07/08/2026 +21 days Advisory disclosed
07/08/2026 +0 days VulDB entry created
07/09/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-55830 (🔒)
GCVE (CVE): GCVE-0-2026-55830
GCVE (VulDB): GCVE-100-377036

Entryinfo

Created: 07/09/2026 00:04
Changes: 07/09/2026 00:04 (56)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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