GHSA-8f6j-263m-g72x: App store server library SignedDataVerifier Accepts Stale OCSP GOOD Vulnerability

MODERATE
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CWE-295 CWE-299
Published
Advisory Summary

GHSA-8f6j-263m-g72x is a MODERATE signeddataverifier accepts stale ocsp good vulnerability (CWE-295: Improper Certificate Validation) affecting App store server library libraries in the PyPI ecosystem. The issue involves signeddataverifier accepts stale ocsp good responses and can bypass certificate revocation checks. Remediation is available by upgrading affected packages to version 3.1.2.

GHSA-8f6j-263m-g72x at a Glance

CVE Identifier N/A
GHSA Identifier GHSA-8f6j-263m-g72x
Severity MODERATE
CVSS v3.1 Base Score N/A
CWE Classification CWE-295: Improper Certificate Validation
Affected Product App store server library
Package Ecosystem PyPI
Published Date
Last Updated

How to Fix GHSA-8f6j-263m-g72x

To remediate this vulnerability, upgrade all affected App store server library dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

app-store-server-library fixed: 3.1.2 
pip install app-store-server-library>=3.1.2
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

pip show app-store-server-library

How to Check if You Are Affected

To determine whether your Python environment is affected by GHSA-8f6j-263m-g72x, inspect your installed packages using pip:

pip show app-store-server-library

Analyze the terminal output to locate any version of App store server library in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 3.1.2), your application is affected.

Note: The pip show app-store-server-library command checks currently installed packages in your active Python environment.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-295: Improper Certificate Validation, where the product does not validate, or incorrectly validates, a certificate. In App store server library, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

### Summary `SignedDataVerifier` attempts to perform online revocation checking when `enable_online_checks=True`, but its OCSP validation logic accepts stale `GOOD` responses as valid indefinitely. In `appstoreserverlibrary/signed_data_verifier.py`, `_ChainVerifier.check_ocsp_status()` verifies the OCSP response signature and CertID match, but never validates the freshness window carried by `producedAt`, `thisUpdate`, or `nextUpdate`. As a result, a previously valid signed OCSP `GOOD` response can be replayed after it is expired, and the library will still treat the certificate as good. If an App Store signing certificate or intermediate is ever revoked, applications using this library with online checks enabled can continue accepting JWS objects signed with the revoked key as long as a stale signed OCSP response is replayed.

GHSA-8f6j-263m-g72x Affected App store server library Versions

1 component(s)
Fixed Versions:
3.1.2
Product / Package Ecosystem Affected Versions Fixed Version
app-store-server-library
pypi/app-store-server-library
PyPI
≥ 0.2.0
< 3.1.2
3.1.2

References

GitHub Advisory / Wiki ADVISORY
https://github.com/apple/app-store-server-library-python/security/advisories/GHSA-8f6j-263m-g72x
App store server library Source Repository REPOSITORY
https://github.com/apple/app-store-server-library-python

Frequently Asked Questions

What is GHSA-8f6j-263m-g72x?
GHSA-8f6j-263m-g72x is a security vulnerability in App store server library involving SignedDataVerifier accepts stale OCSP GOOD responses and can bypass certificate revocation checks under CWE-295: Improper Certificate Validation.
Which App store server library versions are affected?
Affected versions include releases prior to 3.1.2 across affected packages: app-store-server-library.
What version fixes GHSA-8f6j-263m-g72x?
Upgrading to 3.1.2 (or the latest patched release for your respective branch) resolves the vulnerability.
Is app-store-server-library affected?
Yes, app-store-server-library is affected in releases prior to 3.1.2. Upgrade your dependency to 3.1.2 or later.
What CWE is associated with GHSA-8f6j-263m-g72x?
GHSA-8f6j-263m-g72x is classified under CWE-295: Improper Certificate Validation (The product does not validate, or incorrectly validates, a certificate.).
How can I check PyPI dependencies for GHSA-8f6j-263m-g72x?
Run the dependency tree command: 'pip show app-store-server-library'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-8f6j-263m-g72x",
  "modified" : "2026-07-13T23:49:14Z",
  "published" : "2026-07-13T23:49:14Z",
  "aliases" : [ ],
  "summary" : "Apple App Store Server Python Library: SignedDataVerifier accepts stale OCSP GOOD responses and can bypass certificate revocation checks",
  "details" : "### Summary\n`SignedDataVerifier` attempts to perform online revocation checking when `enable_online_checks=True`, but its OCSP validation logic accepts stale `GOOD` responses as valid indefinitely. In `appstoreserverlibrary/signed_data_verifier.py`, `_ChainVerifier.check_ocsp_status()` verifies the OCSP response signature and CertID match, but never validates the freshness window carried by `producedAt`, `thisUpdate`, or `nextUpdate`.\n\nAs a result, a previously valid signed OCSP `GOOD` response can be replayed after it is expired, and the library will still treat the certificate as good. If an App Store signing certificate or intermediate is ever revoked, applications using this library with online checks enabled can continue accepting JWS objects signed with the revoked key as long as a stale signed OCSP response is replayed.",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "app-store-server-library"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0.2.0"
      }, {
        "fixed" : "3.1.2"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 3.1.1"
    }
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/apple/app-store-server-library-python/security/advisories/GHSA-8f6j-263m-g72x"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/apple/app-store-server-library-python"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-295", "CWE-299" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-07-13T23:49:14Z",
    "nvd_published_at" : null
  }
}