Hiredis is a minimalistic C client library for the Redis database. In affected versions Hiredis is vulnurable to integer overflow if provided maliciously crafted or corrupted `RESP` `mult-bulk` protocol data. When parsing `multi-bulk` (array-like) replies, hiredis fails to check if `count * sizeof(redisReply*)` can be represented in `SIZE_MAX`. If it can not, and the `calloc()` call doesn't itself make this check, it would result in a short allocation and subsequent buffer overflow. Users of hiredis who are unable to update may set the [maxelements](https://github.com/redis/hiredis#reader-max-array-elements) context option to a value small enough that no overflow is possible.
CVSS Details
- CVSS 3.1 Base Score: 8.8
- CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Alpine Linux | alpine-linux-upgrade-hiredis | Mar 21, 2024 | Oct 4, 2021 | |
| Amazon Linux Ami 2 | amazon-linux-ami-2-upgrade-hiredisamazon-linux-ami-2-upgrade-hiredis-debuginfoamazon-linux-ami-2-upgrade-hiredis-devel | Sep 28, 2023 | Oct 4, 2021 | |
| Debian | debian-upgrade-hiredis | Nov 29, 2021 | Oct 4, 2021 | |
| Freebsd | freebsd-upgrade-package-hiredis | Nov 4, 2022 | Apr 29, 2022 | |
| Gentoo Linux | gentoo-linux-upgrade-dev-libs-hiredisgentoo-linux-upgrade-dev-python-hiredis | Oct 31, 2022 | Oct 4, 2021 | |
| Suse | — | suse-upgrade-hiredissuse-upgrade-hiredis-develsuse-upgrade-libhiredis0_13 | Dec 7, 2021 | Oct 4, 2021 |
| Ubuntu | no-fix-ubuntu-package | Jun 26, 2025 | Oct 4, 2021 |
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