title: Denial-of-Service in gRPC
description: There exists an vulnerability causing an abort() to be called in gRPC.
The following headers cause gRPC's C++ implementation to abort() when called via http2:
te: x (x != trailers)
:scheme: x (x != http, https)
grpclb_client_stats: x (x == anything)
On top of sending one of those headers, a later header must be sent that gets the total header size past 8KB. We recommend upgrading past git commit 2485fa94bd8a723e5c977d55a3ce10b301b437f8 or v1.53 and above.
problem types: CWE-617 Reachable Assertion
affected:
{
defaultStatus: unaffected
product: gRPC
repo: https://github.com/grpc/grpc
vendor: Google
versions:
lessThan: 1.53, status: affected, version: 1.51, versionType: custom
}
metrics:
cvssV3_1: [
attackComplexity: LOW
attackVector: NETWORK
availabilityImpact: HIGH
baseScore: 7.5
baseSeverity: HIGH
confidentialityImpact: NONE
integrityImpact: NONE
privilegesRequired: NONE
scope: UNCHANGED
userInteraction: NONE
vectorString: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
version: 3.1
]
format: CVSS
scenarios: GENERAL
solutions: Fixes available in these releases:
- 1.52.2:  https://github.com/grpc/grpc/releases/tag/v1.52.2 https://github.com/grpc/grpc/releases/tag/v1.52.2
- 1.53.1:  https://github.com/grpc/grpc/releases/tag/v1.53.1 https://github.com/grpc/grpc/releases/tag/v1.53.1
- 1.54.2:  https://github.com/grpc/grpc/releases/tag/v1.54.2 https://github.com/grpc/grpc/releases/tag/v1.54.2
- 1.55.0:  https://github.com/grpc/grpc/releases/tag/v1.55.0 https://github.com/grpc/grpc/releases/tag/v1.55.0