CVE-2023-35945: Envoy vulnerable to HTTP/2 memory leak in nghttp2 codec

Published Jun 27, 2023
·
Updated

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.

Affected Software

13 affected componentsFixes available
redhat/envoy<1.26.3
1.26.3
redhat/envoy<1.25.8
1.25.8
redhat/envoy<1.24.9
1.24.9
redhat/envoy<1.23.11
1.23.11
Envoyproxy Envoy<1.23.11
Envoyproxy Envoy>=1.24.0<1.24.9
Envoyproxy Envoy>=1.25.0<1.25.8
Envoyproxy Envoy>=1.26.0<1.26.3
nghttp2 nghttp2<1.55.1
Microsoft cbl2 nghttp2 1.46.0-3
Microsoft cbl2 cmake 3.21.4-8
Microsoft cbl2 nodejs 16.20.2-2
Microsoft cbl2 nodejs18 18.17.1-2

Event History

Jul 13, 2023
CVE Published
via MITRE·08:41 PM
Data Sourced
via MITRE·08:41 PM
DescriptionSeverityWeakness
Data Sourced
09:15 PM
DescriptionWeakness
Jul 31, 2023
Data Sourced
via Microsoft·07:00 AM
DescriptionSeverityWeakness
Data Sourced
via Microsoft·07:00 AM
Affected Software
Updated
via Microsoft·07:00 AM
Affected Software
Updated
via Microsoft·07:00 AM
DescriptionSeverity
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Frequently Asked Questions

1

What is CVE-2023-35945?

CVE-2023-35945 is a vulnerability in Envoy's HTTP/2 codec that may leak a header map and bookkeeping structures.

2

What is the severity of CVE-2023-35945?

CVE-2023-35945 has a severity rating of 7.5 (High).

3

How does CVE-2023-35945 affect Envoy?

CVE-2023-35945 affects Envoy versions up to and including 1.26.3.

4

How can I fix CVE-2023-35945?

To fix CVE-2023-35945, upgrade to Envoy version 1.26.3 or apply the appropriate patch provided by Red Hat.

5

Where can I find more information about CVE-2023-35945?

You can find more information about CVE-2023-35945 in the references provided: [Ref 1](https://github.com/nghttp2/nghttp2/blob/e7f59406556c80904b81b593d38508591bb7523a/lib/nghttp2_session.c#L3346), [Ref 2](https://github.com/envoyproxy/envoy/security/advisories/GHSA-jfxv-29pc-x22r), [Ref 3](https://access.redhat.com/errata/RHSA-2023:4624)

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