CVE-2026-33620 — pinchtab
MEDIUMCVE-2026-33620 is a medium-severity (CVSS 4.3) CWE-598 vulnerability in github.com/pinchtab/pinchtab. A fix is available for github.com/pinchtab/pinchtab — see the affected versions and patch details below.
PinchTab: API Bearer Token Exposed in URL Query Parameter via Server Logs and Intermediary Systems
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-33620.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2026-33620 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,333 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
github.com/pinchtab/pinchtabReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
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.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/pinchtab/pinchtab | ≥ 0.7.8&&< 0.8.4 | 0.8.4go get github.com/pinchtab/pinchtab@v0.8.4 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/pinchtab/pinchtab, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/pinchtab/pinchtab to 0.8.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-33620 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-33620 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-33620. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-33620 in your dependencies?
O3 Security finds CVE-2026-33620 across Go dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.