CVE-2021-32761highCWE-125CWE-680

CVE-2021-32761: high-severity vulnerability in redis

Integer overflow issues with *BIT commands on 32-bit systems

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33Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 7.5epss 30%
In short

Redis servers on 32-bit systems have a flaw in bit manipulation commands that can cause integer overflow, potentially allowing attackers to corrupt memory, steal data, or execute malicious code remotely.

Technical detail

An integer overflow vulnerability in Redis *BIT* commands on 32-bit platforms allows remote attackers to trigger buffer overflow by modifying the proto-max-bulk-len configuration parameter and sending specially crafted bit commands, leading to heap corruption, information disclosure, or code execution.

Summary generated and translated by AI from the official description.
Redis is an in-memory database that persists on disk. A vulnerability involving out-of-bounds read and integer overflow to buffer overflow exists starting with version 2.2 and prior to versions 5.0.13, 6.0.15, and 6.2.5. On 32-bit systems, Redis `*BIT*` command are vulnerable to integer overflow that can potentially be exploited to corrupt the heap, leak arbitrary heap contents or trigger remote code execution. The vulnerability involves changing the default `proto-max-bulk-len` configuration parameter to a very large value and constructing specially crafted commands bit commands. This problem only affects Redis on 32-bit platforms, or compiled as a 32-bit binary. Redis versions 5.0.`3m 6.0.15, and 6.2.5 contain patches for this issue. An additional workaround to mitigate the problem without patching the `redis-server` executable is to prevent users from modifying the `proto-max-bulk-len` configuration parameter. This can be done using ACL to restrict unprivileged users from using the CONFIG SET command.
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Affected products
redis · redis
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