How severe is CVE-2018-6339?

CVE-2018-6339 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2018-6339 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (75th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-6339?

CVE-2018-6339 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-2018-6339?

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

When was CVE-2018-6339 published?

CVE-2018-6339 was published on 2019-06-14 and last updated on 2026-06-17.

CVE-2018-6339

CVE-2018-6339 is a critical-severity vulnerability in Whatsapp with a CVSS 3.x base score of 9.8. 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-119.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 2% (75th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-119
Affected product: Whatsapp
Published: 2019-06-14
Last modified: 2026-06-17

Description

When receiving calls using WhatsApp on Android, a stack allocation failed to properly account for the amount of data being passed in. An off-by-one error meant that data was written beyond the allocated space on the stack. This issue affects WhatsApp for Android starting in version 2.18.180 and was fixed in version 2.18.295. It also affects WhatsApp Business for Android starting in version v2.18.103 and was fixed in version v2.18.150.

Frequently asked questions

What is CVE-2018-6339?: When receiving calls using WhatsApp on Android, a stack allocation failed to properly account for the amount of data being passed in. An off-by-one error meant that data was written beyond the allocated space on the stack. This issue affects WhatsApp for Android starting in version 2.18.180 and was fixed in version 2.18.295. It also affects WhatsApp Business for Android starting in version v2.18.103 and was fixed in version v2.18.150.
How severe is CVE-2018-6339?: CVE-2018-6339 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2018-6339 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (75th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-6339?: CVE-2018-6339 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-2018-6339?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2018-6339 published?: CVE-2018-6339 was published on 2019-06-14 and last updated on 2026-06-17.

References

https://www.facebook.com/security/advisories/cve-2018-6339/

Affected products (2)

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

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