CVE-2021-41099 Integer overflow issue with strings in Redis
An integer overflow in Redis allows heap corruption and potential remote code execution if the proto-max-bulk-len parameter is set to a large value.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2021-41099?
CVE-2021-41099 is a high-severity vulnerability in Debian Debian Linux, published on 4 Oct 2021. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Redis is an open source, in-memory database that persists on disk. An integer overflow bug in the underlying string library can be used to corrupt the heap and potentially result with denial of service or remote code execution. The vulnerability involves changing the default proto-max-bulk-len configuration parameter to a very large value and constructing specially crafted network payloads or commands. The problem is fixed in Redis versions 6.2.6, 6.0.16 and 5.0.14. 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.
Which versions are affected by CVE-2021-41099?
3 open source packages ship an affected version, including keydb, redis and valkey. It affects 5 products.
| Package | Affected | Fixed in |
|---|---|---|
keydb Bitnami | From 5.0.0 | 5.0.14, 6.0.16, 6.2.6 |
redis Bitnami | From 5.0.0 | 5.0.14, 6.0.16, 6.2.6 |
valkey Bitnami | From 5.0.0 | 5.0.14, 6.0.16, 6.2.6 |
Products include Debian Debian Linux, Fedoraproject Fedora, Netapp Management Services for Element Software and Netapp Hci, Oracle Communications Operations Monitor, Redis Redis.
How do I fix CVE-2021-41099?
Upgrade keydb to a fixed version for your release line: 5.0.14, 6.0.16 or 6.2.6.
Is CVE-2021-41099 being exploited?
There is no known exploitation of CVE-2021-41099 in the wild and no public exploit code.
Other vulnerabilities in Debian Debian Linux
Sources
Also known as ALPINE-CVE-2021-41099, AZL-6853, BIT-keydb-2021-41099, BIT-redis-2021-41099, BIT-valkey-2021-41099, CLEANSTART-2026-HA19484 and 3 more.