Ubuntu Security Notice 4113-1 - Stefan Eissing discovered that the HTTP/2 implementation in Apache did not properly handle upgrade requests from HTTP/1.1 to HTTP/2 in some situations. A remote attacker could use this to cause a denial of service. This issue only affected Ubuntu 18.04 LTS and Ubuntu 19.04. Craig Young discovered that a memory overwrite error existed in Apache when performing HTTP/2 very early pushes in some situations. A remote attacker could use this to cause a denial of service. This issue only affected Ubuntu 18.04 LTS and Ubuntu 19.04. Various other issues were also addressed.
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