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The header of a push-pull state message contains a count of nodes and user state length. As an optimization, both of these fields are used to pre-allocate memory to receive the remote state before copying it off the wire. But if the header mismatches the actual state, a very small pull-push state message (or at least one below the message size limit) can be used to consume excess memory on the receiver. Limit the memory allocated such that the maximum amount allocated cannot exceed the maximum actual size of the push-pull state, either in number of nodes or size of the user state. Ref: https://hashicorp.atlassian.net/browse/SECVULN-42161 Ref: https://hashicorp.atlassian.net/browse/NMD-1523
jrasell
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A max incarnation in a suspect/dead/alive message overflows refute() and lets one message permanently evict a node. Ignore incarnations above a limit on ingestion, the same way hashicorp#357 bounds the push-pull header. Fixes hashicorp#358.
joakimhellum
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Jul 7, 2026
A max incarnation in a suspect/dead/alive message overflows refute() and lets one message permanently evict a node. Ignore incarnations above a limit on ingestion, the same way hashicorp#357 bounds the push-pull header. Fixes hashicorp#358.
joakimhellum
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Jul 7, 2026
A max incarnation in a suspect/dead/alive message overflows refute() and lets one message permanently evict a node. Ignore incarnations above a limit on ingestion, the same way hashicorp#357 bounds the push-pull header. Fixes hashicorp#358.
This was referenced Jul 8, 2026
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Jul 8, 2026
readUserMsg sizes make([]byte, header.UserMsgLen) from the wire header with no bound, so a small userMsg frame declaring a large length forces a large allocation on the receiver. This is the userMsg path of the same issue hashicorp#357 fixed for push-pull state.
joakimhellum
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Jul 9, 2026
readUserMsg sizes make([]byte, header.UserMsgLen) from the wire header with no bound, so a small userMsg frame declaring a large length forces a large allocation on the receiver. This is the userMsg path of the same issue hashicorp#357 fixed for push-pull state.
joakimhellum
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Jul 9, 2026
A max incarnation in a suspect/dead/alive message overflows refute() and lets one message permanently evict a node. Ignore incarnations above a limit on ingestion, the same way hashicorp#357 bounds the push-pull header. Fixes hashicorp#358.
joakimhellum
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Jul 9, 2026
A max incarnation in a suspect/dead/alive message overflows refute() and lets one message permanently evict a node. Ignore incarnations above a limit on ingestion, the same way hashicorp#357 bounds the push-pull header. Fixes hashicorp#358.
joakimhellum
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Jul 10, 2026
A max incarnation in a suspect/dead/alive message overflows refute() and lets one message permanently evict a node. Ignore incarnations above a limit on ingestion, the same way hashicorp#357 bounds the push-pull header. Fixes hashicorp#358.
joakimhellum
added a commit
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that referenced
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Jul 10, 2026
A max incarnation in a suspect/dead/alive message overflows refute() and lets one message permanently evict a node. Ignore incarnations above a limit on ingestion, the same way hashicorp#357 bounds the push-pull header. Fixes hashicorp#358.
joakimhellum
added a commit
to pigeon-as/memberlist
that referenced
this pull request
Jul 10, 2026
A max incarnation in a suspect/dead/alive message overflows refute() and lets one message permanently evict a node. Ignore incarnations above a limit on ingestion, the same way hashicorp#357 bounds the push-pull header. Fixes hashicorp#358.
joakimhellum
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to pigeon-as/memberlist
that referenced
this pull request
Jul 10, 2026
A max incarnation in a suspect/dead/alive message overflows refute() and lets one message permanently evict a node. Ignore incarnations above a limit on ingestion, the same way hashicorp#357 bounds the push-pull header. Fixes hashicorp#358.
joakimhellum
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Jul 11, 2026
A max incarnation in a suspect/dead/alive message overflows refute() and lets one message permanently evict a node. Ignore incarnations above a limit on ingestion, the same way hashicorp#357 bounds the push-pull header. Fixes hashicorp#358.
joakimhellum
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that referenced
this pull request
Jul 11, 2026
A max incarnation in a suspect/dead/alive message overflows refute() and lets one message permanently evict a node. Ignore incarnations above a limit on ingestion, the same way hashicorp#357 bounds the push-pull header. Fixes hashicorp#358.
joakimhellum
added a commit
to pigeon-as/memberlist
that referenced
this pull request
Jul 11, 2026
A max incarnation in a suspect/dead/alive message overflows refute() and lets one message permanently evict a node. Ignore incarnations above a limit on ingestion, the same way hashicorp#357 bounds the push-pull header. Fixes hashicorp#358.
joakimhellum
added a commit
to pigeon-as/memberlist
that referenced
this pull request
Jul 11, 2026
A max incarnation in a suspect/dead/alive message overflows refute() and lets one message permanently evict a node. Ignore incarnations above a limit on ingestion, the same way hashicorp#357 bounds the push-pull header. Fixes hashicorp#358.
joakimhellum
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Jul 13, 2026
A max incarnation in a suspect/dead/alive message overflows refute() and lets one message permanently evict a node. Ignore incarnations above a limit on ingestion, the same way hashicorp#357 bounds the push-pull header. Fixes hashicorp#358.
joakimhellum
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Jul 14, 2026
A max incarnation in a suspect/dead/alive message overflows refute() and lets one message permanently evict a node. Ignore incarnations above a limit on ingestion, the same way hashicorp#357 bounds the push-pull header. Fixes hashicorp#358.
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The header of a push-pull state message contains a count of nodes and user state length. As an optimization, both of these fields are used to pre-allocate memory to receive the remote state before copying it off the wire. But if the header mismatches the actual state, a very small pull-push state message (or at least one below the message size limit) can be used to consume excess memory on the receiver.
Limit the memory allocated such that the maximum amount allocated cannot exceed the maximum actual size of the push-pull state, either in number of nodes or size of the user state.
Ref: https://hashicorp.atlassian.net/browse/SECVULN-42161
Ref: https://hashicorp.atlassian.net/browse/NMD-1523