CVE-2024-27919: HTTP/2: memory exhaustion due to CONTINUATION frame flood
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.
Classification
CVE ID: CVE-2024-27919
CVSS Base Severity: HIGH
CVSS Base Score: 7.5
CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Affected Products
Vendor: envoyproxy
Product: envoy
Exploit Prediction Scoring System (EPSS)
EPSS Score: 0.05% (probability of being exploited)
EPSS Percentile: 18.45% (scored less or equal to compared to others)
EPSS Date: 2025-03-14 (when was this score calculated)
References
https://github.com/envoyproxy/envoy/security/advisories/GHSA-gghf-vfxp-799rhttps://github.com/envoyproxy/envoy/commit/57a02565532c18eb9df972a3e8974be3ae59f2d5
http://www.openwall.com/lists/oss-security/2024/04/05/3
http://www.openwall.com/lists/oss-security/2024/04/03/16