CVE-2024-27919

HTTP/2: memory exhaustion due to CONTINUATION frame flood

State
Published
Severity
7.5 High
Published
Apr 4, 2024
Updated
Nov 4, 2025
Reserved
Feb 28, 2024

Read the record on cve.org

Description

Envoy is a cloud-native, open-source edge and service proxy. In versions 1.29.0 and 1.29.1, theEnvoy HTTP/2 protocol stack is vulnerable to the flood of CONTINUATION frames. Envoy's HTTP/2 codec does not reset a request when header map limits have been exceeded. This allows an attacker to send an sequence of CONTINUATION frames without the END_HEADERS bit set causing unlimited memory consumption. This can lead to denial of service through memory exhaustion. Users should upgrade to versions 1.29.2 to mitigate the effects of the CONTINUATION flood. Note that this vulnerability is a regression in Envoy version 1.29.0 and 1.29.1 only. As a workaround, downgrade to version 1.28.1 or earlier or disable HTTP/2 protocol for downstream connections.

Scores

CVSSScoreVectorSource
3.17.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HGitHub_M

Weaknesses

  • CWE-390 Detection of Error Condition Without Action

Affected Products

ProductVersions
envoyenvoyproxy
  • >= 1.29.0, < 1.29.2Affected

References

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