CVE-2024-53270: HTTP/1: sending overload crashes when the request is reset beforehand in envoy

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.7% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2024-12-18 · updated 2026-06-17
Weakness: CWE-670

Description

Envoy is a cloud-native high-performance edge/middle/service proxy. In affected versions `sendOverloadError` is going to assume the active request exists when `envoy.load_shed_points.http1_server_abort_dispatch` is configured. If `active_request` is nullptr, only onMessageBeginImpl() is called. However, the `onMessageBeginImpl` will directly return ok status if the stream is already reset leading to the nullptr reference. The downstream reset can actually happen during the H/2 upstream reset. As a result envoy may crash. This issue has been addressed in releases 1.32.3, 1.31.5, 1.30.9, and 1.29.12. Users are advised to upgrade. Users unable to upgrade may disable `http1_server_abort_dispatch` load shed point and/or use a high threshold.

Affected products

envoyproxy envoy: before 1.29.12; from 1.30.0 before 1.30.9; from 1.31.0 before 1.31.5; from 1.32.0 before 1.32.3 — fixed in 1.29.12, 1.30.9, 1.31.5, 1.32.3

How to fix

Upgrade to a fixed version: envoyproxy envoy 1.29.12, 1.30.9, 1.31.5, 1.32.3. Check the vendor advisory for mitigations.

References

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