CVE-2022-29240

Uninitialized memory read in LZ4 decompression leads to authentication bypass in Scylla

Description

Scylla is a real-time big data database that is API-compatible with Apache Cassandra and Amazon DynamoDB. When decompressing CQL frame received from user, Scylla assumes that user-provided uncompressed length is correct. If user provides fake length, that is greater than the real one, part of decompression buffer won't be overwritten, and will be left uninitialized. This can be exploited in several ways, depending on the privileges of the user. 1. The main exploit is that an attacker with access to CQL port, but no user account, can bypass authentication, but only if there are other legitimate clients making connections to the cluster, and they use LZ4. 2. Attacker that already has a user account on the cluster can read parts of uninitialized memory, which can contain things like passwords of other users or fragments of other queries / results, which leads to authorization bypass and sensitive information disclosure. The bug has been patched in the following versions: Scylla Enterprise: 2020.1.14, 2021.1.12, 2022.1.0. Scylla Open Source: 4.6.7, 5.0.3. Users unable to upgrade should make sure none of their drivers connect to cluster using LZ4 compression, and that Scylla CQL port is behind firewall. Additionally make sure no untrusted client can connect to Scylla, by setting up authentication and applying workarounds from previous point (firewall, no lz4 compression).

Category

8.1
CVSS
Severity: High
CVSS 3.1 •
EPSS 0.11%
Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com
Affected: scylladb scylla
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2022-29240?
CVE-2022-29240 has been scored as a high severity vulnerability.
How to fix CVE-2022-29240?
To fix CVE-2022-29240, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2022-29240 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2022-29240 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2022-29240?
CVE-2022-29240 affects scylladb scylla.
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