CVE-2021-43825

Summary

Envoy is an open source edge and service proxy, designed for cloud-native applications. Sending a locally generated response must stop further processing of request or response data. Envoy tracks the amount of buffered request and response data and aborts the request if the amount of buffered data is over the limit by sending 413 or 500 responses. However when the buffer overflows while response is processed by the filter chain the operation may not be aborted correctly and result in accessing a freed memory block. If this happens Envoy will crash resulting in a denial of service.

Affected Software

VendorProductVersion RangeStatus
envoyproxyenvoy< 1.18.6affected
envoyproxyenvoy>= 1.19.0, < 1.19.3affected
envoyproxyenvoy>= 1.20.0, < 1.20.2affected
envoyproxyenvoy>= 1.21.0, < 1.21.1affected

Weaknesses

  • CWE-416: CWE-416: Use After Free

ADP Enrichment

CVE Program Container

Additional References

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

References