How severe is CVE-2021-3470?

CVE-2021-3470 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.

Is CVE-2021-3470 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-3470?

CVE-2021-3470 primarily affects Redislabs Redis. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-3470?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-3470 published?

CVE-2021-3470 was published on 2021-03-31 and last updated on 2026-06-17.

CVE-2021-3470

CVE-2021-3470 is a medium-severity vulnerability in Redislabs Redis with a CVSS 3.x base score of 5.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-787.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 5.0
EPSS exploit prediction: 1% (63rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Redislabs Redis
Published: 2021-03-31
Last modified: 2026-06-17

Description

A heap overflow issue was found in Redis in versions before 5.0.10, before 6.0.9 and before 6.2.0 when using a heap allocator other than jemalloc or glibc's malloc, leading to potential out of bound write or process crash. Effectively this flaw does not affect the vast majority of users, who use jemalloc or glibc malloc.

Frequently asked questions

What is CVE-2021-3470?: A heap overflow issue was found in Redis in versions before 5.0.10, before 6.0.9 and before 6.2.0 when using a heap allocator other than jemalloc or glibc's malloc, leading to potential out of bound write or process crash. Effectively this flaw does not affect the vast majority of users, who use jemalloc or glibc malloc.
How severe is CVE-2021-3470?: CVE-2021-3470 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.
Is CVE-2021-3470 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-3470?: CVE-2021-3470 primarily affects Redislabs Redis. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-3470?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-3470 published?: CVE-2021-3470 was published on 2021-03-31 and last updated on 2026-06-17.

References

https://bugzilla.redhat.com/show_bug.cgi?id=1943623

Affected products (4)

cpe:2.3:a:redislabs:redis:*:*:*:*:*:*:*:*
cpe:2.3:a:redislabs:redis:6.2.0:rc1:*:*:*:*:*:*
cpe:2.3:a:redislabs:redis:6.2.0:rc2:*:*:*:*:*:*
cpe:2.3:a:redislabs:redis:6.2.0:rc3:*:*:*:*:*:*

More vulnerabilities in Redislabs Redis

CVE-2015-4335 — Critical (CVSS 10.0): Redis before 2.8.21 and 3.x before 3.0.2 allows remote attackers to execute arbitrary Lua bytecode via the eval command.
CVE-2018-11219 — Critical (CVSS 9.8): An Integer Overflow issue was discovered in the struct library in the Lua subsystem in Redis before 3.2.12, 4.x before…
CVE-2018-11218 — Critical (CVSS 9.8): Memory Corruption was discovered in the cmsgpack library in the Lua subsystem in Redis before 3.2.12, 4.x before…
CVE-2017-15047 — Critical (CVSS 9.8): The clusterLoadConfig function in cluster.c in Redis 4.0.2 allows attackers to cause a denial of service (out-of-bounds…
CVE-2016-8339 — Critical (CVSS 9.8): A buffer overflow in Redis 3.2.x prior to 3.2.4 causes arbitrary code execution when a crafted command is sent. An out…
CVE-2018-12326 — High (CVSS 8.4): Buffer overflow in redis-cli of Redis before 4.0.10 and 5.x before 5.0 RC3 allows an attacker to achieve code execution…

All CVEs affecting Redislabs Redis →

Other CWE-787 (Out-of-bounds Write) vulnerabilities

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CVE-2025-43300 — Critical (CVSS 10.0): An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in iOS 15.8.5 and iPadOS…
CVE-2025-24201 — Critical (CVSS 10.0): An out-of-bounds write issue was addressed with improved checks to prevent unauthorized actions. This issue is fixed in…
CVE-2024-42479 — Critical (CVSS 10.0): llama.cpp provides LLM inference in C/C++. The unsafe `data` pointer member in the `rpc_tensor` structure can cause…
CVE-2024-39791 — Critical (CVSS 10.0): Stack-based buffer overflow vulnerabilities affecting Vonets industrial wifi bridge relays and wifi bridge…

Browse all CWE-787 (Out-of-bounds Write) vulnerabilities →

Threat intelligence

Threat-intel indicators referencing this CVE:

120.48.174.141 (ipv4-addr)