CVE-2021-22964
Published: 14 October 2021
Summary
CVE-2021-22964 is a high-severity Uncontrolled Resource Consumption (CWE-400) vulnerability in Fastify Fastify-Static. Its CVSS base score is 8.8 (High).
Operationally, ranked in the top 41.3% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2021-2236
Vulnerability details
A redirect vulnerability in the `fastify-static` module version >= 4.2.4 and < 4.4.1 allows remote attackers to redirect Mozilla Firefox users to arbitrary websites via a double slash `//` followed by a domain: `http://localhost:3000//a//youtube.com/%2e%2e%2f%2e%2e`.A DOS vulnerability is possible if the…
more
URL contains invalid characters `curl --path-as-is "http://localhost:3000//^/.."`The issue shows up on all the `fastify-static` applications that set `redirect: true` option. By default, it is `false`.
- CWE(s)
Related Threats
No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Limiting concurrent sessions directly prevents uncontrolled resource consumption by capping the number of active sessions per user or account.
Security awareness includes verifying URLs and avoiding untrusted redirects that lead to malicious sites.
Analysis identifies uncontrolled resource consumption indicative of denial-of-service or abuse attempts.
Contingency plan testing includes resource exhaustion scenarios to verify recovery, making it harder for attackers to sustain exploits that cause uncontrolled consumption.
Updated contingency plans include current procedures to detect, contain, and recover from resource exhaustion, limiting an attacker's ability to sustain impact from uncontrolled consumption.
Alternate site allows resumption of operations if resource exhaustion at the primary site is exploited to cause unavailability.
Alternate telecommunications services enable resumption of essential functions when primary services become unavailable due to uncontrolled resource consumption.
The team can analyze and respond to resource exhaustion incidents, reducing the impact of attacks that exploit uncontrolled consumption weaknesses.