# CVE-2026-55954: Missing ID token claim validation in ueberauth_apple allows account takeover

> Attackers can hijack user accounts by replaying unvalidated Apple ID tokens due to missing claim checks in the ueberauth_apple library.

- **Severity:** Critical 9.1 (`CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 14 Jul 2026
- **Updated:** 15 Jul 2026
- **Also known as:** EEF-CVE-2026-55954, GHSA-pxx8-68pc-p9mr

## What is CVE-2026-55954?

CVE-2026-55954 is a critical authentication bypass vulnerability in ueberauth_apple, published on 14 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Authentication Bypass by Spoofing vulnerability in ueberauth ueberauth_apple allows account takeover via unvalidated ID token claims.

The Ueberauth.Strategy.Apple.Token.payload/2 function verifies the JWT signature of the callback id_token against Apple's JWKS but does not validate any registered claims. The iss, aud, exp, and iat claims are read from the token and passed on to Ueberauth.Strategy.Apple.handle_callback!/1, which derives the logged-in user's uid and email directly from the unvalidated sub claim.

An attacker who obtains any Apple-signed ID token bearing the victim's sub (via a captured expired token, or via an ID token issued to a sibling client in the same Apple developer team) can replay it against the vulnerable callback and be authenticated as the victim. The absent exp check makes stolen tokens usable indefinitely, and the absent aud check enables cross-application account takeover across clients that share an Apple developer team.

This issue affects ueberauth_apple: from 0.1.0 before 0.6.2.

Weakness: CWE-290 (Authentication Bypass by Spoofing)

## Which versions are affected by CVE-2026-55954?

1 open source package ship an affected version, including ueberauth_apple.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `ueberauth_apple` | Hex | From 0.1.0 | 0.6.2 |

## How do I fix CVE-2026-55954?

Upgrade ueberauth_apple to 0.6.2 or later.

## Is CVE-2026-55954 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-55954 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-55954 and fix it if it is affected.

What it is: CVE-2026-55954 is a critical authentication bypass vulnerability in ueberauth_apple, published on 14 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-55954 exists.

Affected packages and fixed versions:
- ueberauth_apple (Hex): affected from 0.1.0; fixed in 0.6.2

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/CVE-2026-55954/ (Markdown: https://insights.sbomify.com/CVE-2026-55954/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-55954
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-55954
- OSV: https://osv.dev/vulnerability/CVE-2026-55954

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-55954/
Summaries are generated and may contain mistakes; the official description above is the record.