How severe is CVE-2021-31986?

CVE-2021-31986 has a CVSS 3.x base score of 6.8, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability high.

Is CVE-2021-31986 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-31986?

CVE-2021-31986 primarily affects Axis Axis Os. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-31986?

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

When was CVE-2021-31986 published?

CVE-2021-31986 was published on 2021-10-05 and last updated on 2026-06-17.

CVE-2021-31986

CVE-2021-31986 is a medium-severity vulnerability in Axis Axis Os with a CVSS 3.x base score of 6.8. 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 6.8)
CVSS v2: 4.0
EPSS exploit prediction: 1% (51st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Axis Axis Os
Published: 2021-10-05
Last modified: 2026-06-17

Description

User controlled parameters related to SMTP notifications are not correctly validated. This can lead to a buffer overflow resulting in crashes and data leakage.

Frequently asked questions

What is CVE-2021-31986?: User controlled parameters related to SMTP notifications are not correctly validated. This can lead to a buffer overflow resulting in crashes and data leakage.
How severe is CVE-2021-31986?: CVE-2021-31986 has a CVSS 3.x base score of 6.8, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability high.
Is CVE-2021-31986 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-31986?: CVE-2021-31986 primarily affects Axis Axis Os. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-31986?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-31986 published?: CVE-2021-31986 was published on 2021-10-05 and last updated on 2026-06-17.

References

https://www.axis.com/files/tech_notes/CVE-2021-31986.pdf

Affected products (4)

cpe:2.3:o:axis:axis_os:*:*:*:*:active:*:*:*
cpe:2.3:o:axis:axis_os_2016:*:*:*:*:lts:*:*:*
cpe:2.3:o:axis:axis_os_2018:*:*:*:*:lts:*:*:*
cpe:2.3:o:axis:axis_os_2020:*:*:*:*:lts:*:*:*

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