How severe is CVE-2021-1837?

CVE-2021-1837 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2021-1837 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (39th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-1837?

CVE-2021-1837 primarily affects Apple Ipados. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-1837?

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

When was CVE-2021-1837 published?

CVE-2021-1837 was published on 2021-09-08 and last updated on 2026-06-17.

CVE-2021-1837

CVE-2021-1837 is a medium-severity vulnerability in Apple Ipados 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-295.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 4.3
EPSS exploit prediction: 0% (39th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-295
Affected product: Apple Ipados
Published: 2021-09-08
Last modified: 2026-06-17

Description

A certificate validation issue was addressed. This issue is fixed in iOS 14.5 and iPadOS 14.5. An attacker in a privileged network position may be able to alter network traffic.

Frequently asked questions

What is CVE-2021-1837?: A certificate validation issue was addressed. This issue is fixed in iOS 14.5 and iPadOS 14.5. An attacker in a privileged network position may be able to alter network traffic.
How severe is CVE-2021-1837?: CVE-2021-1837 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2021-1837 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (39th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-1837?: CVE-2021-1837 primarily affects Apple Ipados. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-1837?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-1837 published?: CVE-2021-1837 was published on 2021-09-08 and last updated on 2026-06-17.

References

https://support.apple.com/en-us/HT212317

Affected products (2)

cpe:2.3:o:apple:ipados:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:iphone_os:*:*:*:*:*:*:*:*

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