High severity · published Jul 21, 2021
CVE-2021-32761
Redis is an in-memory database that persists on disk
7.5
CVSS
36.6%
EPSS
No
On KEV
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 vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
High
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)36.6% · higher than 98% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
RE
Redis · Redis
2.2.0 before 5.0.13; 6.0 before 6.0.15; 6.2.0 before 6.2.5 · source: NVD
DL
Debian Linux · Debian
9.0; 10.0; 11.0 · source: NVD
FE
Fedora · Fedoraproject
33; 34 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-32761
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-32761
Third Party Advisory
https://github.com/redis/redis/security/advisories/GHSA-8wxq-j7rp-g8wj
Mailing List
https://lists.debian.org/debian-lts-announce/2021/07/msg00017.html
Mailing List
https://lists.debian.org/debian-lts-announce/2021/08/msg00026.html
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6O7AUOROBYGP5IMGJPC5HZ3R2RB6GZ5X/
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VGX7RRAWGXWXEAKJTQYSDSBO2BC3SAHD/
Third Party Advisory
https://security.gentoo.org/glsa/202209-17
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