# GHSA-8f6j-263m-g72x: `SignedDataVerifier` attempts to perform online revocation checking when `enable_online_checks=True`, but its OCSP validation lo

> Attackers can bypass certificate revocation checks in Apple App Store Server Python Library by replaying stale OCSP responses when online checks are enabled.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 13 Jul 2026

## What is GHSA-8f6j-263m-g72x?

GHSA-8f6j-263m-g72x is a vulnerability in app-store-server-library, published on 13 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

### 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.

## Which versions are affected by GHSA-8f6j-263m-g72x?

2 open source packages ship an affected version, including app-store-server-library.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `app-store-server-library` | PyPI | From 0.2.0 | 3.1.2 |
| `app-store-server-library` | PyPI | From 0.2.0 | 3.1.2 |

## How do I fix GHSA-8f6j-263m-g72x?

Upgrade app-store-server-library to 3.1.2 or later.

## Is GHSA-8f6j-263m-g72x being exploited?

There is no known exploitation of GHSA-8f6j-263m-g72x in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for GHSA-8f6j-263m-g72x and fix it if it is affected.

What it is: GHSA-8f6j-263m-g72x is a vulnerability in app-store-server-library, published on 13 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of GHSA-8f6j-263m-g72x in the wild and no public exploit code.

Affected packages and fixed versions:
- app-store-server-library (PyPI): affected from 0.2.0; fixed in 3.1.2
- app-store-server-library (PyPI): affected from 0.2.0; fixed in 3.1.2

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/GHSA-8f6j-263m-g72x/ (Markdown: https://insights.sbomify.com/GHSA-8f6j-263m-g72x/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/GHSA-8f6j-263m-g72x

---
From sbomify Insights: https://insights.sbomify.com/GHSA-8f6j-263m-g72x/
Summaries are generated and may contain mistakes; the official description above is the record.