CVE-2021-22963
CVE-2021-22963 is a medium-severity vulnerability in Fastify Fastify-static with a CVSS 3.x base score of 6.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-601.
Key facts
- Severity: Medium (CVSS 3.x base score 6.1)
- CVSS v2: 5.8
- EPSS exploit prediction: 1% (63rd percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-601
- Affected product: Fastify Fastify-static
- Published:
- Last modified:
Description
A redirect vulnerability in the fastify-static module version < 4.2.4 allows remote attackers to redirect users to arbitrary websites via a double slash // followed by a domain: http://localhost:3000//google.com/%2e%2e.The issue shows up on all the fastify-static applications that set redirect: true option. By default, it is false.
Frequently asked questions
- What is CVE-2021-22963?
- A redirect vulnerability in the fastify-static module version < 4.2.4 allows remote attackers to redirect users to arbitrary websites via a double slash // followed by a domain: http://localhost:3000//google.com/%2e%2e.The issue shows up on all the fastify-static applications that set redirect: true option. By default, it is false.
- How severe is CVE-2021-22963?
- CVE-2021-22963 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
- Is CVE-2021-22963 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-22963?
- CVE-2021-22963 affects Fastify Fastify-static. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-22963?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2021-22963 published?
- CVE-2021-22963 was published on 2021-10-14 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:a:fastify:fastify-static:*:*:*:*:*:*:*:*
More vulnerabilities in Fastify Fastify-static
- CVE-2021-22964 — High (CVSS 8.8): A redirect vulnerability in the `fastify-static` module version >= 4.2.4 and < 4.4.1 allows remote attackers to…
- CVE-2026-6414 — Medium (CVSS 5.9): @fastify/static versions 8.0.0 through 9.1.0 decode percent-encoded path separators (%2F) before filesystem resolution,…
- CVE-2026-6410 — Medium (CVSS 5.3): @fastify/static versions 8.0.0 through 9.1.0 allow path traversal when directory listing is enabled via the list…
All CVEs affecting Fastify Fastify-static →
Other CWE-601 (Open Redirect) vulnerabilities
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- CVE-2019-25282 — Critical (CVSS 9.8): V-SOL GPON/EPON OLT Platform v2.03 contains an open redirect vulnerability in the script that allows attackers to…
- CVE-2020-36912 — Critical (CVSS 9.8): Plexus anblick Digital Signage Management 3.1.13 contains an open redirect vulnerability in the 'PantallaLogin' script…
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