CVE-2021-32761

HIGHCVSS 7.5/10EPSS 31.05%

Last modified

CVE-2021-32761 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. 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. EPSS estimates a 31.05% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1
7.5/10

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

EPSS Probability
31.05%

98.0th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

VendorProductVersions
RedislabsRedis>= 2.2.0, < 5.0.13
RedislabsRedis>= 6.0, < 6.0.15
RedislabsRedis>= 6.2.0, < 6.2.5
DebianDebian Linux9.0
DebianDebian Linux10.0
DebianDebian Linux11.0
FedoraprojectFedora33
FedoraprojectFedora34

References

Timeline

Published
Last Modified
Status
Modified

Frequently Asked Questions

What is CVE-2021-32761?
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.
How severe is CVE-2021-32761?
CVE-2021-32761 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 31.05% probability of exploitation in the next 30 days.
How do I fix CVE-2021-32761?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-32761?

Run a free Strix scan to check your systems for this vulnerability.

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Source: NVD / NIST