How severe is CVE-2021-35944?

CVE-2021-35944 has a CVSS 3.x base score of 7.5, rated high 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 high.

Is CVE-2021-35944 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-35944?

CVE-2021-35944 primarily affects Couchbase Couchbase Server. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-35944?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-35944 published?

CVE-2021-35944 was published on 2021-09-29 and last updated on 2026-06-17.

CVE-2021-35944

CVE-2021-35944 is a high-severity vulnerability in Couchbase Couchbase Server with a CVSS 3.x base score of 7.5. 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-120.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 1% (60th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-120
Affected product: Couchbase Couchbase Server
Published: 2021-09-29
Last modified: 2026-06-17

Description

Couchbase Server 6.5.x, 6.6.x through 6.6.2, and 7.0.0 has a Buffer Overflow. A specially crafted network packet sent from an attacker can crash memcached.

Frequently asked questions

What is CVE-2021-35944?: Couchbase Server 6.5.x, 6.6.x through 6.6.2, and 7.0.0 has a Buffer Overflow. A specially crafted network packet sent from an attacker can crash memcached.
How severe is CVE-2021-35944?: CVE-2021-35944 has a CVSS 3.x base score of 7.5, rated high 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 high.
Is CVE-2021-35944 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-35944?: CVE-2021-35944 primarily affects Couchbase Couchbase Server. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-35944?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-35944 published?: CVE-2021-35944 was published on 2021-09-29 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:couchbase:couchbase_server:*:*:*:*:*:*:*:*
cpe:2.3:a:couchbase:couchbase_server:7.0.0:*:*:*:*:*:*:*

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