PoC Index

CVE-2023-27493

CRITICAL 9.1EPSS 0.5%

Envoy is an open source edge and service proxy designed for cloud-native applications. Prior to versions 1.26.0, 1.25.3, 1.24.4, 1.23.6, and 1.22.9, Envoy does not sanitize or escape request properties when generating request headers. This can lead to characters that are illegal in header values to be sent to the upstream service. In the worst case, it can cause upstream service to interpret the original request as two pipelined requests, possibly bypassing the intent of Envoy’s security policy. Versions 1.26.0, 1.25.3, 1.24.4, 1.23.6, and 1.22.9 contain a patch. As a workaround, disable adding request headers based on the downstream request properties, such as downstream certificate properties.

CVSS v3.1
9.1 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
CVSS v3.1
8.1 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N
EPSS
0.51% chance of exploitation in the next 30 days, 41th percentile
Published
2023-04-04
Updated
2025-02-11

Proof-of-concept exploits (1)

References

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