CVE-2022-0637 is a medium-severity (CVSS 6.1) Open Redirect vulnerability in pollbot. 1 public exploit reference exists, so weaponization risk is real. A fix is available for pollbot — see the affected versions and patch details below.
open redirect in pollbot
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2022-0637.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2022-0637 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 385,987 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Real-World Exposure
pollbotReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
(From https://bugzilla.mozilla.org/show_bug.cgi?id=1753838)
Summary: There was an open redirection vulnerability in the path of:
https://pollbot.services.mozilla.com/ and https://pollbot.stage.mozaws.net/
Description: An attacker can redirect anyone to malicious sites.
Steps To Reproduce: Type in this URL:
https://pollbot.services.mozilla.com/%0a/evil.com/
It redirects to that website
evil.com
evil.com was used as an example but this could be any website. Note, the /%0a/ and trailing / are required.
Supporting Material/References: https://cheatsheetseries.owasp.org/cheatsheets/Unvalidated_Redirects_and_Forwards_Cheat_Sheet.html
Impact
Attackers can serve malicious websites that steal passwords or download ransomware to their victims machine due to a redirect and there are a heap of other attack vectors.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | pollbot | all versions | 1.4.6pip install --upgrade 'pollbot==1.4.6' |
Affected Products
pollbotmozillaResearch use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for pollbot, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update pollbot to 1.4.6 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2022-0637 is resolved across your whole dependency graph.
Workarounds
Stop reflecting attacker-controlled destinations: resolve every redirect target against an allowlist of paths or hosts you own, prefer a server-side key over a full URL in the request, and reject absolute URLs entirely where the flow only ever needs a relative one.
Frequently Asked Questions
Is CVE-2022-0637 in your dependencies?
Find it across PyPI, including transitive dependencies.