How severe is CVE-2021-24027?

CVE-2021-24027 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 high, integrity none, and availability none.

Is CVE-2021-24027 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (89th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-24027?

CVE-2021-24027 primarily affects Whatsapp. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-24027?

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-2021-24027 published?

CVE-2021-24027 was published on 2021-04-06 and last updated on 2026-06-17.

CVE-2021-24027

CVE-2021-24027 is a high-severity vulnerability in Whatsapp 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-524.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 4% (89th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-524
Affected product: Whatsapp
Published: 2021-04-06
Last modified: 2026-06-17

Description

A cache configuration issue prior to WhatsApp for Android v2.21.4.18 and WhatsApp Business for Android v2.21.4.18 may have allowed a third party with access to the device’s external storage to read cached TLS material.

Frequently asked questions

What is CVE-2021-24027?: A cache configuration issue prior to WhatsApp for Android v2.21.4.18 and WhatsApp Business for Android v2.21.4.18 may have allowed a third party with access to the device’s external storage to read cached TLS material.
How severe is CVE-2021-24027?: CVE-2021-24027 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 high, integrity none, and availability none.
Is CVE-2021-24027 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (89th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-24027?: CVE-2021-24027 primarily affects Whatsapp. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-24027?: 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-2021-24027 published?: CVE-2021-24027 was published on 2021-04-06 and last updated on 2026-06-17.

References

https://www.whatsapp.com/security/advisories/2021/

Affected products (2)

cpe:2.3:a:whatsapp:whatsapp:*:*:*:*:*:android:*:*
cpe:2.3:a:whatsapp:whatsapp_business:*:*:*:*:*:android:*:*

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