CVE-2026-33620 PinchTab: API Bearer Token Exposed in URL Query Parameter via Server Logs and Intermediary Systems
Attackers can steal API tokens exposed in URLs via logs or intermediaries, potentially gaining unauthorized control over the AI browser server.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-33620?
CVE-2026-33620 is a medium-severity vulnerability in pinchtab, published on 26 Mar 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
PinchTab is a standalone HTTP server that gives AI agents direct control over a Chrome browser. PinchTab `v0.7.8` through `v0.8.3` accepted the API token from a `token` URL query parameter in addition to the `Authorization` header. When a valid API credential is sent in the URL, it can be exposed through request URIs recorded by intermediaries or client-side tooling, such as reverse proxy access logs, browser history, shell history, clipboard history, and tracing systems that capture full URLs. This issue is an unsafe credential transport pattern rather than a direct authentication bypass. It only affects deployments where a token is configured and a client actually uses the query-parameter form. PinchTab's security guidance already recommended `Authorization: Bearer <token>`, but `v0.8.3` still accepted `?token=` and included first-party flows that generated and consumed URLs containing the token. This was addressed in v0.8.4 by removing query-string token authentication and requiring safer header- or session-based authentication flows.
Weakness: CWE-598
Which versions are affected by CVE-2026-33620?
3 open source packages ship an affected version, including github.com/pinchtab/pinchtab. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
github.com/pinchtab/pinchtab Go | From 0.7.8 | 0.8.4 |
github.com/pinchtab/pinchtab Go | From 0.7.8 | 0.8.4 |
github.com/pinchtab/pinchtab Go | From 0.7.8 | 0.8.4 |
Products include Pinchtab Pinchtab.
How do I fix CVE-2026-33620?
Upgrade github.com/pinchtab/pinchtab to 0.8.4 or later.
Is CVE-2026-33620 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-33620 exists.
Other vulnerabilities in pinchtab
- CVE-2026-30834 PinchTab: SSRF with Full Response Exfiltration via Download Handler
- CVE-2026-33623 PinchTab: OS Command Injection via Profile Name in Windows Cleanup Routine Enables Arbitrary Command Execution
- CVE-2026-33622 A PinchTab Security Policy Bypass in /wait Allows Arbitrary JavaScript Execution
- CVE-2026-33081 PinchTab has Blind SSRF via browser-side redirect bypass in /download URL validation
- CVE-2026-33621 PinchTab: Unapplied Rate Limiting Middleware Allows Unbounded Brute-Force of API Token
Sources
Also known as GHSA-mrqc-3276-74f8, GO-2026-4822.