How severe is CVE-2026-5402?

CVE-2026-5402 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-5402 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (31st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-5402?

CVE-2026-5402 affects Wireshark. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-5402?

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.

Does CVE-2026-5402 have an EU (EUVD) identifier?

Yes. CVE-2026-5402 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-26318.

When was CVE-2026-5402 published?

CVE-2026-5402 was published on 2026-04-30 and last updated on 2026-06-30.

CVE-2026-5402

CVE-2026-5402 is a high-severity vulnerability in Wireshark with a CVSS 3.x base score of 8.8. 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-122.

Key facts

Severity: High (CVSS 3.x base score 8.8)
EPSS exploit prediction: 0% (31st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-26318
Weakness: CWE-122
Affected product: Wireshark
Published: 2026-04-30
Last modified: 2026-06-30

Description

TLS protocol dissector heap overflow in Wireshark 4.6.0 to 4.6.4 allows denial of service and possible code execution

Frequently asked questions

What is CVE-2026-5402?: TLS protocol dissector heap overflow in Wireshark 4.6.0 to 4.6.4 allows denial of service and possible code execution
How severe is CVE-2026-5402?: CVE-2026-5402 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-5402 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (31st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-5402?: CVE-2026-5402 affects Wireshark. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-5402?: 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.
Does CVE-2026-5402 have an EU (EUVD) identifier?: Yes. CVE-2026-5402 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-26318.
When was CVE-2026-5402 published?: CVE-2026-5402 was published on 2026-04-30 and last updated on 2026-06-30.

References

Affected products (1)

cpe:2.3:a:wireshark:wireshark:*:*:*:*:*:*:*:*

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