# google-oauth-java-client improperly verifies cryptographic signature

Advisory record · `GHSA-hw42-3568-wj87`

- **Identifiers:** `GHSA-hw42-3568-wj87` · `CVE-2021-22573`
- **State:** Confirmed
- **Severity:** CVSS 8.7 High
- **Critical:** No
- **Weakness (CWE):** [CWE-347](https://cwe.mitre.org/data/definitions/347.html)
- **Tags:** [Weak cryptography or TLS](https://agentprime.io/advisories/tag/weak-crypto.md)
- **Published:** 9 Apr 2024
- **Updated:** 10 Apr 2024
- **Reviewed by a person:** No

Published by the GitHub Advisory Database at 9 Apr 2024, 15:11 UTC. agentprime has not analysed this yet, so whether it affects any app is not known.

## Affected packages

- `com.google.oauth-client:google-oauth-client` (Maven): affected `>=1.16.0-rc, <1.33.3`; fixed in `1.33.3`

## Machine-written summary

Summary written by Claude Haiku from the source advisory. Not reviewed by a person.

> The Maven package com.google.oauth-client:google-oauth-client, versions 1.16.0-rc up to but not including 1.33.3, has an IdTokenVerifier whose verify method checks claims before validating the signature. An attacker who can supply a token with a modified payload, such as a changed email or phone number, can get it accepted by the library. Upgrade to version 1.33.3 or later.

Written 8 Nov 2026.

## Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

## Severity and exploitation

- 8.7 High, CVSS 3.1: `CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N`, from CNA (Google)

- **CISA KEV:** Not listed.
- **EPSS:** 0.0030, the 23rd percentile, on 14 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

## Timeline

- 31 Oct 2026, 15:13 UTC: First seen by agentprime
- 31 Oct 2026, 15:13 UTC: [Confirmed by OSV](https://osv.dev/vulnerability/GHSA-hw42-3568-wj87)

## Sources

- [GitHub Advisory Database: GHSA-hw42-3568-wj87](https://github.com/advisories/GHSA-hw42-3568-wj87)
- [OSV: GHSA-hw42-3568-wj87](https://osv.dev/vulnerability/GHSA-hw42-3568-wj87)
- <https://github.com/googleapis/google-oauth-java-client/security/advisories/GHSA-hw42-3568-wj87>
- <https://nvd.nist.gov/vuln/detail/CVE-2021-22573>
- <https://github.com/googleapis/google-oauth-java-client/pull/872>
- <https://github.com/googleapis/google-oauth-java-client/commit/c634ad4e31cac322bb1aa8a9feb0569749011bf0>
- <https://github.com/googleapis/google-oauth-java-client>

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.

## Check whether this affects you

A Match means an installed version is in the affected range above. Most don’t affect the app; agentprime hasn’t analysed this one yet.

- With the agentprime MCP server (<https://api.agentprime.io/mcp>), ask your agent to check the project: `check_lockfile` sends a lockfile, `check_packages` a list of installed packages, and both return the Matches and the upgrades that clear them. `get_advisory` returns this record. Setup: <https://agentprime.io/mcp.md>
- In a browser: <https://agentprime.io/check/> reads your lockfile in the browser, never uploading it.
- Whether it touches your code, with file and line: the Claude Code plugin, <https://agentprime.io/plugin.md>
- As JSON: <https://api.agentprime.io/v1/advisories/GHSA-hw42-3568-wj87>, or `POST https://api.agentprime.io/v1/match` with your packages (<https://agentprime.io/api.md>)

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The web page: <https://agentprime.io/advisories/GHSA-hw42-3568-wj87/>. Everything for agents: <https://agentprime.io/llms.txt>.