Denial of Service (DoS) Affecting package, versions >=1.0.0 <1.20.0



    Attack Complexity Low
    Availability High

    Threat Intelligence

    EPSS 0.18% (55th percentile)
Expand this section
7.5 high

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  • published 6 Nov 2022
  • disclosed 3 Nov 2022
  • credit OSS-Fuzz

How to fix?

Upgrade apple/swift-nio-http2 to version 1.20.0 or higher.


apple/swift-nio-http2 is a HTTP/2 support for SwiftNIO.

Affected versions of this package are vulnerable to Denial of Service (DoS). This can be caused by a network peer sending a specially crafted HTTP/2 frame, due to a logical error when parsing a HTTP/2 HEADERS or HTTP/2 PUSH_PROMISE frame where the frame contains padding information without any other data.


Denial of Service (DoS) describes a family of attacks, all aimed at making a system inaccessible to its intended and legitimate users.

Unlike other vulnerabilities, DoS attacks usually do not aim at breaching security. Rather, they are focused on making websites and services unavailable to genuine users resulting in downtime.

One popular Denial of Service vulnerability is DDoS (a Distributed Denial of Service), an attack that attempts to clog network pipes to the system by generating a large volume of traffic from many machines.

When it comes to open source libraries, DoS vulnerabilities allow attackers to trigger such a crash or crippling of the service by using a flaw either in the application code or from the use of open source libraries.

Two common types of DoS vulnerabilities:

  • High CPU/Memory Consumption- An attacker sending crafted requests that could cause the system to take a disproportionate amount of time to process. For example, commons-fileupload:commons-fileupload.

  • Crash - An attacker sending crafted requests that could cause the system to crash. For Example, npm ws package