CVE-2023-35945High· 7.5▾ MidnightPoC availableEnvoy is a cloud-native high-performance edge/middle/service proxy. Envoy’s HTTP/2 codec may leak a header map and bookkeeping structures upon receiving `RST_STREAM` immediately followed by the `GOAWAY` frames from an upstream server. In…
▾ Midnight zone — Critical, or high with PoC / in-the-wild
impact 41.3 · likelihood 0.3 · exploitation 12
A public proof-of-concept already exists for this vulnerability — see Exploit availability below.
Stakeholder-Specific Vulnerability Categorization from CISA's ADP record at CVE.org: whether exploitation is observed, whether an attack can be automated, and how much of the system is at stake.
Exploit-prediction probability, daily snapshots since Oct 15.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via NVD
Last analysed / modified upstream
1.3%
Exploit / PoC code exists
1.3% → 1.7%
Envoy is a cloud-native high-performance edge/middle/service proxy. Envoy’s HTTP/2 codec may leak a header map and bookkeeping structures upon receiving RST_STREAM immediately followed by the GOAWAY frames from an upstream server. In nghttp2, cleanup of pending requests due to receipt of the GOAWAY frame skips de-allocation of the bookkeeping structure and pending compressed header. The error return [code path] is taken if connection is already marked for not sending more requests due to GOAWAY frame. The clean-up code is right after the return statement, causing memory leak. Denial of service through memory exhaustion. This vulnerability was patched in versions(s) 1.26.3, 1.25.8, 1.24.9, 1.23.11.
envoy < 1.23.11envoy >= 1.24.0, < 1.24.9envoy >= 1.25.0, < 1.25.8envoy >= 1.26.0, < 1.26.3nghttp2 < 1.55.1Upgrade past the affected range:
envoy 1.26.3nghttp2 1.55.1Field changes observed since this record was first indexed.
Connected by shared product, vendor, weakness, or advisory.
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