Vulnerability · Published Sep 15, 2022 · Assigned by GitHub_M
CVE-2022-29240Uninitialized memory read in LZ4 decompression leads to authentication bypass in Scylla
High 8.1
In plain English
A high-severity security flaw in scylla from scylladb. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 1.3% (higher than 70% of all known vulnerabilities).
Official 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).
Affected products (as reported)
Weakness: CWE-908 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
References
- https://github.com/scylladb/scylla/security/advisories/GHSA-25pq-rrqm-6fmr x_refsource_CONFIRM
- https://github.com/scylladb/scylladb/issues/11476 x_refsource_MISC
- https://github.com/scylladb/scylladb/commit/1c2eef384da439b0457b6d71c7e37d7268e471cb x_refsource_MISC