How severe is CVE-2021-3655?

CVE-2021-3655 has a CVSS 3.x base score of 3.3, rated low severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2021-3655 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (23rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-3655?

CVE-2021-3655 primarily affects Redhat Enterprise Linux. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-3655?

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

When was CVE-2021-3655 published?

CVE-2021-3655 was published on 2021-08-05 and last updated on 2026-06-17.

CVE-2021-3655

CVE-2021-3655 is a low-severity vulnerability in Redhat Enterprise Linux with a CVSS 3.x base score of 3.3. 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-20.

Key facts

Severity: Low (CVSS 3.x base score 3.3)
CVSS v2: 2.1
EPSS exploit prediction: 0% (23rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Redhat Enterprise Linux
Published: 2021-08-05
Last modified: 2026-06-17

Description

A vulnerability was found in the Linux kernel in versions prior to v5.14-rc1. Missing size validations on inbound SCTP packets may allow the kernel to read uninitialized memory.

Frequently asked questions

What is CVE-2021-3655?: A vulnerability was found in the Linux kernel in versions prior to v5.14-rc1. Missing size validations on inbound SCTP packets may allow the kernel to read uninitialized memory.
How severe is CVE-2021-3655?: CVE-2021-3655 has a CVSS 3.x base score of 3.3, rated low severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2021-3655 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (23rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-3655?: CVE-2021-3655 primarily affects Redhat Enterprise Linux. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-3655?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-3655 published?: CVE-2021-3655 was published on 2021-08-05 and last updated on 2026-06-17.

References

Affected products (4)

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.14:-:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*

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