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CVE-2019-9511

Some HTTP/2 implementations are vulnerable to window size manipulation and stream prioritization manipulation, potentially leading to a denial of service

High7.5EPSS 59.5%
Published
Updated
Reserved
Assigned by
certcc

Description

Some HTTP/2 implementations are vulnerable to window size manipulation and stream prioritization manipulation, potentially leading to a denial of service. The attacker requests a large amount of data from a specified resource over multiple streams. They manipulate window size and stream priority to force the server to queue the data in 1-byte chunks. Depending on how efficiently this data is queued, this can consume excess CPU, memory, or both.

Scores

CVSS scores of CVE-2019-9511, by who scored it
Scored byCVSSScoreVector
certccCNA (assigner)3.0High7.5CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVDNVD · Modified3.1High7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS (exploitation in 30 days)
59.5% · top 0.9% of all CVEs (6 Nov 2026)
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The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.5.

Weakness

Affected products

  • n/a

    • affected n/a

References (47)

Sources

The same CVE in the primary databases and aggregators, to check against.

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Record last updated .