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No exploitation reportedFix available

CVE-2021-32628

No exploitation reported by the sources we read.

  • Published2021-10-04
  • WeaknessCWE-190 · CWE-680

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

Redis is an open source, in-memory database that persists on disk. An integer overflow bug in the ziplist data structure used by all versions of Redis can be exploited to corrupt the heap and potentially result with remote code execution. The vulnerability involves modifying the default ziplist configuration parameters (hash-max-ziplist-entries, hash-max-ziplist-value, zset-max-ziplist-entries or zset-max-ziplist-value) to a very large value, and then constructing specially crafted commands to create very large ziplists. The problem is fixed in Redis versions 6.2.6, 6.0.16, 5.0.14. An additional workaround to mitigate the problem without patching the redis-server executable is to prevent users from modifying the above configuration parameters. This can be done using ACL to restrict unprivileged users from using the CONFIG SET command.

Timeline

dates in UTC
  1. 2021-10-0418:15CVE publishedNVD
  2. 2026-10-2319:23EPSS crossed 10 %FIRST EPSS

Observed activity

isMalicious corpus · updated 2026-10-23 21:37 UTC
Indicators tagged with this CVE, per day0 indicators over 7 days
Block these indicators
  • Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2021-32628?format=txt
  • CSV export: https://api.ismalicious.com/edl/cve/CVE-2021-32628?format=csv
  • TAXII collection of exploited CVEs
  • The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD · OSV
Fedoraproject fedora
BranchAffectedFixed in
33.x= 33no fix published
34.x= 34no fix published
35.x= 35no fix published
Oracle communications operations monitor
BranchAffectedFixed in
4.3= 4.3no fix published
4.4= 4.4no fix published
5.0= 5.0no fix published
Redis
BranchAffectedFixed in
6.2≥ 6.2.0, < 6.2.66.2.6
6.0≥ 6.0.0, < 6.0.166.0.16
5.0≥ 5.0.0, < 5.0.145.0.14

3 more products in the sources.

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Distribution builds and vendor advisories

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Packages

  • redisAlmaLinux:8all versions · fixed in 5.0.3-5.module_el8.4.0+2583+b9845322and 2 other packages
  • redisAlmaLinux:8all versions · fixed in 5.0.3-5.module_el8.5.0+66+fc19ec12and 1 other package
  • redisAlmaLinux:8all versions · fixed in 6.0.9-5.module_el8.4.0+2584+1bb0d2aaand 2 other packages
  • redisAlmaLinux:8all versions · fixed in 6.0.9-5.module_el8.5.0+67+a3c431d9and 1 other package

Full record on NVD

Fix

Advisories and patches

Detection

Nuclei template
none so far
ProjectDiscovery
Exploit-DB
no entry
Exploit-DB
Proof-of-concept repositories
none listed
PoC-in-GitHub

Sources

  • CNACVSS 3.17.5read 2026-10-23
  • NVDCVSS 3.17.5read 2026-10-23
  • NVDCVSS 2.06read 2026-10-23
  • CNAweakness (CWE)CWE-190, CWE-680read 2026-10-23
  • NVDweakness (CWE)CWE-190read 2026-10-23
  • FIRST EPSSEPSS score13.5 %read 2026-10-23
  • OSVaffected packages—

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Published
2021-10-04
Last Modified
2026-06-17
NVD status
Modified

Frequently asked questions

What is CVE-2021-32628?

Redis is an open source, in-memory database that persists on disk. An integer overflow bug in the ziplist data structure used by all versions of Redis can be exploited to corrupt the heap and potentially result with remote code execution. The vulnerability involves modifying the default ziplist configuration parameters (hash-max-ziplist-entries, hash-max-ziplist-value, zset-max-ziplist-entries or zset-max-ziplist-value) to a very large value, and then constructing specially crafted commands to create very large ziplists. The problem is fixed in Redis versions 6.2.6, 6.0.16, 5.0.14. An additional workaround to mitigate the problem without patching the redis-server executable is to prevent users from modifying the above configuration parameters. This can be done using ACL to restrict unprivileged users from using the CONFIG SET command.

Is CVE-2021-32628 actively exploited?

Active exploitation of CVE-2021-32628 has not been confirmed. Its EPSS score was 13.5% on 2026-10-23, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2021-32628?

CVE-2021-32628 has a CVSS v3 base score of 7.5 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H.

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