CVE-2025-62409

Summary

Envoy is a cloud-native, open source edge and service proxy. Prior to 1.36.1, 1.35.5, 1.34.9, and 1.33.10, large requests and responses can potentially trigger TCP connection pool crashes due to flow control management in Envoy. It will happen when the connection is closing but upstream data is still coming, resulting in a buffer watermark callback nullptr reference. The vulnerability impacts TCP proxy and HTTP 1 & 2 mixed use cases based on ALPN. This vulnerability is fixed in 1.36.1, 1.35.5, 1.34.9, and 1.33.10.

Affected Software

VendorProductVersion RangeStatus
envoyproxyenvoy>= 1.36.0, < 1.36.1affected
envoyproxyenvoy>= 1.35.0, < 1.35.5affected
envoyproxyenvoy>= 1.34.0, < 1.34.9affected
envoyproxyenvoy< 1.33.10affected

Weaknesses

  • CWE-476: CWE-476: NULL Pointer Dereference

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: poc
    • Automatable: yes
    • Technical Impact: partial

Additional References

References