CVE-2021-32628

Description

An integer overflow issue was found in the redis ziplist data structure. The vulnerability involves modifying the default ziplist configuration parameters (hash-max-ziplist-entries, hash-max-ziplist-value, zset-max-ziplist-entries or zset-max-ziplist-value) to a very large value, and then constructing specially crafted commands to create very large ziplists. This flaw allows a remote attacker to corrupt the heap and potentially trigger remote code execution. The highest threat from this vulnerability is to confidentiality, integrity, as well as system availability.

Mitigation

The flaw can be mitigated by disallowing usage of the CONFIG SET command via ACL configuration. This will prevent clients from setting the above configuration parameters. Please see https://redis.io/topics/acl for more information on how to do this.

Common Vulnerability Scoring System (CVSS) Score Details

Info alert:Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score7.57.57.5
Attack VectorNetworkNetworkNetwork
Attack ComplexityHighHighHigh
Privileges RequiredLowLowLow
User InteractionNoneNoneNone
ScopeUnchangedUnchangedUnchanged
ConfidentialityHighHighHigh
Integrity ImpactHighHighHigh
Availability ImpactHighHighHigh

Vector

Red Hat: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

NVD: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

cve.org: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

Understanding the Weakness (CWE)

Integrity

Technical Impact: Modify Memory; Execute Unauthorized Code or Commands

Write operations could cause memory corruption. In some cases, an adversary can modify control data such as return addresses in order to execute unexpected code.

Availability

Technical Impact: DoS: Crash, Exit, or Restart

Attempting to access out-of-range, invalid, or unauthorized memory could cause the product to crash.

Other

Technical Impact: Unexpected State

Subsequent write operations can produce undefined or unexpected results.

Acknowledgements

Upstream acknowledges sundb as the original reporter.

Frequently Asked Questions

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