CVE-2021-21309
Redis 32-bit Integer Overflow Remote Code Execution Vulnerability
Description
Redis is an open-source, in-memory database that persists on disk. In affected versions of Redis an integer overflow bug in 32-bit Redis version 4.0 or newer could be exploited to corrupt the heap and potentially result with remote code execution. Redis 4.0 or newer uses a configurable limit for the maximum supported bulk input size. By default, it is 512MB which is a safe value for all platforms. If the limit is significantly increased, receiving a large request from a client may trigger several integer overflow scenarios, which would result with buffer overflow and heap corruption. We believe this could in certain conditions be exploited for remote code execution. By default, authenticated Redis users have access to all configuration parameters and can therefore use the “CONFIG SET proto-max-bulk-len” to change the safe default, making the system vulnerable. **This problem only affects 32-bit Redis (on a 32-bit system, or as a 32-bit executable running on a 64-bit system).** The problem is fixed in version 6.2, and the fix is back ported to 6.0.11 and 5.0.11. Make sure you use one of these versions if you are running 32-bit Redis. An additional workaround to mitigate the problem without patching the redis-server executable is to prevent clients from directly executing `CONFIG SET`: Using Redis 6.0 or newer, ACL configuration can be used to block the command. Using older versions, the `rename-command` configuration directive can be used to rename the command to a random string unknown to users, rendering it inaccessible. Please note that this workaround may have an additional impact on users or operational systems that expect `CONFIG SET` to behave in certain ways.
INFO
Published Date :
Feb. 26, 2021, 10:15 p.m.
Last Modified :
Oct. 19, 2022, 1:21 p.m.
Source :
[email protected]
Remotely Exploitable :
Yes !
Impact Score :
5.9
Exploitability Score :
2.8
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2021-21309
.
URL | Resource |
---|---|
https://github.com/redis/redis/commit/c992857618db99776917f10bf4f2345a5fdc78b0 | Patch Third Party Advisory |
https://github.com/redis/redis/pull/8522 | Patch Third Party Advisory |
https://github.com/redis/redis/security/advisories/GHSA-hgj8-vff2-7cjf | Third Party Advisory |
https://security.gentoo.org/glsa/202103-02 | Third Party Advisory |
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2021-21309
vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2021-21309
vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by [email protected]
May. 14, 2024
Action Type Old Value New Value -
Modified Analysis by [email protected]
Oct. 19, 2022
Action Type Old Value New Value Changed Reference Type https://security.gentoo.org/glsa/202103-02 No Types Assigned https://security.gentoo.org/glsa/202103-02 Third Party Advisory -
CVE Modified by [email protected]
Mar. 31, 2021
Action Type Old Value New Value Added Reference https://security.gentoo.org/glsa/202103-02 [No Types Assigned] -
Reanalysis by [email protected]
Mar. 16, 2021
Action Type Old Value New Value Removed CVSS V2 NIST (AV:N/AC:L/Au:N/C:P/I:P/A:P) Added CVSS V2 NIST (AV:N/AC:L/Au:S/C:P/I:P/A:P) Removed CVSS V3.1 NIST AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Added CVSS V3.1 NIST AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H -
Initial Analysis by [email protected]
Mar. 08, 2021
Action Type Old Value New Value Added CVSS V2 NIST (AV:N/AC:L/Au:N/C:P/I:P/A:P) Added CVSS V3.1 NIST AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Changed Reference Type https://github.com/redis/redis/commit/c992857618db99776917f10bf4f2345a5fdc78b0 No Types Assigned https://github.com/redis/redis/commit/c992857618db99776917f10bf4f2345a5fdc78b0 Patch, Third Party Advisory Changed Reference Type https://github.com/redis/redis/pull/8522 No Types Assigned https://github.com/redis/redis/pull/8522 Patch, Third Party Advisory Changed Reference Type https://github.com/redis/redis/security/advisories/GHSA-hgj8-vff2-7cjf No Types Assigned https://github.com/redis/redis/security/advisories/GHSA-hgj8-vff2-7cjf Third Party Advisory Added CPE Configuration OR *cpe:2.3:a:redislabs:redis:*:*:*:*:*:*:*:* versions from (including) 4.0 up to (excluding) 5.0.11 *cpe:2.3:a:redislabs:redis:*:*:*:*:*:*:*:* versions from (including) 6.0.0 up to (excluding) 6.0.11
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2021-21309
is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2021-21309
weaknesses.
Exploit Prediction
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.
0.57 }} 0.02%
score
0.77279
percentile