How severe is CVE-2017-6420?

CVE-2017-6420 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2017-6420 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (69th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2017-6420?

CVE-2017-6420 affects Clamav. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2017-6420?

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

When was CVE-2017-6420 published?

CVE-2017-6420 was published on 2017-08-07 and last updated on 2026-06-17.

CVE-2017-6420

CVE-2017-6420 is a medium-severity vulnerability in Clamav with a CVSS 3.x base score of 5.5. 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-416.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
CVSS v2: 4.3
EPSS exploit prediction: 1% (69th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-416
Affected product: Clamav
Published: 2017-08-07
Last modified: 2026-06-17

Description

The wwunpack function in libclamav/wwunpack.c in ClamAV 0.99.2 allows remote attackers to cause a denial of service (use-after-free) via a crafted PE file with WWPack compression.

Frequently asked questions

What is CVE-2017-6420?: The wwunpack function in libclamav/wwunpack.c in ClamAV 0.99.2 allows remote attackers to cause a denial of service (use-after-free) via a crafted PE file with WWPack compression.
How severe is CVE-2017-6420?: CVE-2017-6420 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2017-6420 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (69th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2017-6420?: CVE-2017-6420 affects Clamav. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2017-6420?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2017-6420 published?: CVE-2017-6420 was published on 2017-08-07 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:clamav:clamav:0.99.2:*:*:*:*:*:*:*

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