#VU54656 Resource exhaustion in gRPC Swift - CVE-2021-36155

Vulnerability identifier: #VU54656

Vulnerability risk: Medium

CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-36155

CWE-ID: CWE-400

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
gRPC Swift
Web applications / Modules and components for CMS

Vendor: grpc

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to application does not properly control consumption of internal resources within the LengthPrefixedMessageReader function. A remote attacker can trigger resource exhaustion and perform a denial of service (DoS) attack.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

gRPC Swift: 1.0.0 - 1.1.1

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External links
https://github.com/grpc/grpc-swift/security/advisories/GHSA-rxmj-hg9v-vp3p
https://github.com/grpc/grpc-swift/releases
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=35303

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.