CVE-2021-21354
Open redirect in pollbot
Pollbot is open source software which "frees its human masters from the toilsome task of polling for the state of things during the Firefox release process." In Pollbot before version 1.4.4 there is an open redirection vulnerability in the path of "https://pollbot.services.mozilla.com/". An attacker can redirect anyone to malicious sites. To Reproduce type in this URL: "https://pollbot.services.mozilla.com//evil.com/". Affected versions will redirect to that website when you inject a payload like "//evil.com/". This is fixed in version 1.4.4.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Required
What an attacker can affect
- Confidentiality
- None
- Integrity
- High
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
Open redirect in pollbot
Pollbot is open source software which "frees its human masters from the toilsome task of polling for the state of things during the Firefox release process." In Pollbot before version 1.4.4 there is an open redirection vulnerability in the path of "https://pollbot.services.mozilla.com/". An attacker can redirect anyone to malicious sites. To Reproduce type in this URL: "https://pollbot.services.mozilla.com//evil.com/". Affected versions will redirect to that website when you inject a payload like "//evil.com/". This is fixed in version 1.4.4.
- Record
CVE-2021-21354- CVSS 3.1
- 7.4 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:H/A:N - Weakness
- CWE-601
- Updated
- 2026-11-02
EUVDEUVD-2021-8677
Pollbot is open source software which "frees its human masters from the toilsome task of polling for the state of things during the Firefox release process." In Pollbot before version 1.4.4 there is an open redirection vulnerability in the path of "https://pollbot.services.mozilla.com/". An attacker can redirect anyone to malicious sites. To Reproduce type in this URL: "https://pollbot.services.mozilla.com//evil.com/". Affected versions will redirect to that website when you inject a payload like "//evil.com/". This is fixed in version 1.4.4.
- Record
EUVD-2021-8677- CVSS 3.1
- 7.4 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:H/A:N - Updated
- 2026-11-03
NVD
Pollbot is open source software which "frees its human masters from the toilsome task of polling for the state of things during the Firefox release process." In Pollbot before version 1.4.4 there is an open redirection vulnerability in the path of "https://pollbot.services.mozilla.com/". An attacker can redirect anyone to malicious sites. To Reproduce type in this URL: "https://pollbot.services.mozilla.com//evil.com/". Affected versions will redirect to that website when you inject a payload like "//evil.com/". This is fixed in version 1.4.4.
- Record
CVE-2021-21354- CVSS 3.1
- 7.4 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:H/A:N - CVSS 3.1
- 6.1 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - CVSS 2.0
- 5.8 Medium
AV:N/AC:M/Au:N/C:P/I:P/A:N - Weakness
- CWE-601
- Updated
- 2026-11-02
OSV
Pollbot is open source software which "frees its human masters from the toilsome task of polling for the state of things during the Firefox release process." In Pollbot before version 1.4.4 there is an open redirection vulnerability in the path of "https://pollbot.services.mozilla.com/". An attacker can redirect anyone to malicious sites. To Reproduce type in this URL: "https://pollbot.services.mozilla.com//evil.com/". Affected versions will redirect to that website when you inject a payload like "//evil.com/". This is fixed in version 1.4.4.
- Record
CVE-2021-21354- CVSS 3.1
- 6.1 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-21354 is a high vulnerability (CVSS 7.4) in Mozilla Pollbot, published March 8, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.36%, the 71st percentile. No source names a fixed version.
References
github.com/mozilla/PollBot/security/advisories/GHSA-jhgx-wmq8-jc24
bugzilla.mozilla.org/show_bug.cgi?id=1694684
cheatsheetseries.owasp.org/cheatsheets/Unvalidated_Redirects_and_Forwards_Cheat_Sheet.html