Critical

HTTP/2 DoS Attacks: Ping, Reset, and Settings Floods

  • Disclosed: 14.03.2022
  • Updated: 11.10.2026 12:19

Impact

Twisted web servers that utilize the optional HTTP/2 support suffer from the following flow-control related vulnerabilities:

Ping flood: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-9512 Reset flood: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-9514 Settings flood: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-9515

A Twisted web server supports HTTP/2 requests if you've installed the http2 optional dependency set.

Workarounds

There are no workarounds.

References

https://github.com/Netflix/security-bulletins/blob/master/advisories/third-party/2019-002.md

For more information

If you have any questions or comments about this advisory:

Affected software

Click a technology to see all vulnerabilities affecting it.

PlatformPackageVulnerable versionsFixed in
Python (PyPI) twisted < 19.10.0 19.10.0

References

CVSS score -
Weakness (CWE)
-
Platform
Python (PyPI)
Package
twisted
Disclosed
14.03.2022
Updated
11.10.2026 12:19

Sources and licenses

OSV / GitHub Advisory Database - GHSA-32gv-6cf3-wcmq - CC BY 4.0

Vulnerability history: twisted

All published vulnerabilities of this package (Python (PyPI)), newest first. Shows whether this is a one-off slip or a package that needs watching.

All (17) in the archive
Total entries
17
First → latest
06.2019 10.2026
Without a fix
1
Exploited in attacks
0

Severity breakdown

  • Critical 5
  • High 4
  • Medium 8

Disclosures per year

  1. 2019: 3
  2. 2020: 3
  3. 2021: 0
  4. 2022: 6
  5. 2023: 1
  6. 2024: 2
  7. 2025: 0
  8. 2026: 2
Severity:
  1. Critical · 8.1 CVE-2022-24801 < 22.4.0 22.4.0
  2. HTTP/2 DoS Attacks: Ping, Reset, and Settings Floods this entry
    Critical ghsa-32gv-6cf3-wcmq < 19.10.0 19.10.0
  3. High · 7.5 CVE-2022-21716 >= 21.7.0, < 22.2.0 22.2.0
  4. High · 7.5 CVE-2022-21712 >= 11.1.0, < 22.1.0 22.1.0
  5. Critical · 9.8 CVE-2020-10109 < 20.3.0 20.3.0
  6. Critical · 9.8 CVE-2020-10108 < 20.3.0 20.3.0
  7. High · 7.5 CVE-2014-7143 >= 14.0.0, < 14.0.1 14.0.1
  8. Critical · 7.4 CVE-2019-12855 < 19.7.0rc1 19.7.0rc1

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