#VU46905 Buffer overflow in brotli - CVE-2020-8927

Vulnerability identifier: #VU46905

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-2020-8927

CWE-ID: CWE-120

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
brotli
Other software / Other software solutions

Vendor: Google

Description

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

A buffer overflow exists in the Brotli library versions prior to 1.0.8 where an attacker controlling the input length of a "one-shot" decompression request to a script can trigger a crash, which happens when copying over chunks of data larger than 2 GiB. It is recommended to update your Brotli library to 1.0.8 or later. If one cannot update, we recommend to use the "streaming" API as opposed to the "one-shot" API, and impose chunk size limits.

Mitigation
Install update from vendor's website.

Vulnerable software versions

brotli: 1.0.0 - 1.0.7

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External links
https://github.com/google/brotli/releases/tag/v1.0.9

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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.