CVE-2021-32625 | Redis vulnerability in STRALGO LCS on 32-bit systems

Redis is an open source (BSD licensed), in-memory data structure store, used as a database, cache, and message broker. An integer overflow bug in Redis version 6.0 or newer, could be exploited using the STRALGO LCS command to corrupt the heap and potentially result with remote code execution. This is a result of an incomplete fix by CVE-2021-29477. The problem is fixed in version 6.2.4 and 6.0.14. An additional workaround to mitigate the problem without patching the redis-server executable is to use ACL configuration to prevent clients from using the STRALGO LCS command. On 64 bit systems which have the fixes of CVE-2021-29477 (6.2.3 or 6.0.13), it is sufficient to make sure that the proto-max-bulk-len config parameter is smaller than 2GB (default is 512MB).

Published: 2021-06-02 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-32625 is rated Moderate Risk (61.5/100): CVSS High severity, with high exploitation likelihood (EPSS 4.38%, 90th percentile). EPSS ranks this CVE among the most likely to be exploited in the near term. High exploitation likelihood—assess exposure and prioritize remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2021-32625

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-19 4.34% 4.38% +0.04%
2 2026-06-15 3.75% 4.34% +0.59%
3 2026-06-04 — 3.75% —

Full EPSS history (20 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-32625

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.6 5.9 [email protected]
8.8 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.8 5.9 [email protected]
6.5 2.0 MEDIUM
AV:N/AC:L/Au:S/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:S)
A single authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 8.0 6.4 [email protected]

Weakness enumeration for CVE-2021-32625

OS Trackers for CVE-2021-32625

vendor priority summary link
alpine high CVE-2021-32625: 1 source package rows (redis); 16 state rows across 8 repos (3.17-main, 3.18-main, 3.19-main, 3.20-community, 3.21-community, 3.22-community, edge-community, edge-main); fixed 8, open 8. https://security.alpinelinux.org/vuln/CVE-2021-32625
debian not yet assigned CVE-2021-32625 not yet assigned priority: Debian including 1 source packages (redis), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2021-32625
redhat high — https://access.redhat.com/security/cve/CVE-2021-32625
suse high — https://www.suse.com/security/cve/CVE-2021-32625/
ubuntu medium CVE-2021-32625 medium priority: Ubuntu including 1 source packages (redis), 16 status rows across 16 suites (bionic, focal, groovy, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): not-affected 11, ignored 2, needed 2, released 1. https://ubuntu.com/security/CVE-2021-32625

Affected software / configurations for CVE-2021-32625

Vendor Product Version Raw CPE
redislabs redis >= 6.0.0, < 6.0.14 cpe:2.3:a:redislabs:redis:*:*:*:*:*:*:x84:*
redislabs redis >= 6.2.0, < 6.2.4 cpe:2.3:a:redislabs:redis:*:*:*:*:*:*:x84:*
fedoraproject fedora 33 cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*
fedoraproject fedora 34 cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*

References for CVE-2021-32625

cvelogic Threat Intelligence