How severe is CVE-2026-63447?

CVE-2026-63447 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 none, integrity none, and availability high.

Is CVE-2026-63447 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (48th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-63447?

CVE-2026-63447 affects Oisf Suricata. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-63447?

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-2026-63447 published?

CVE-2026-63447 was published on 2026-09-18 and last updated on 2026-09-28.

CVE-2026-63447

CVE-2026-63447 is a high-severity vulnerability in Oisf Suricata 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-407.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (48th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-407
Affected product: Oisf Suricata
Published: 2026-09-18
Last modified: 2026-09-28

Description

Suricata is a network Intrusion Detection System, Intrusion Prevention System and Network Security Monitoring engine. From 8.0.5 until 8.0.6, the FTP parser in src/app-layer-ftp.c can continue allocating transactions after app-layer.protocols.ftp.max-tx is reached while processing one large chunk of FTP command data. The oversized transaction list is repeatedly processed with quadratic complexity after the too_many_transactions event, allowing crafted FTP traffic to degrade packet processing, reduce monitoring visibility, or cause denial of service. This issue is fixed in version 8.0.6.

Frequently asked questions

What is CVE-2026-63447?: Suricata is a network Intrusion Detection System, Intrusion Prevention System and Network Security Monitoring engine. From 8.0.5 until 8.0.6, the FTP parser in src/app-layer-ftp.c can continue allocating transactions after app-layer.protocols.ftp.max-tx is reached while processing one large chunk of FTP command data. The oversized transaction list is repeatedly processed with quadratic complexity after the too_many_transactions event, allowing crafted FTP traffic to degrade packet processing, reduce monitoring visibility, or cause denial of service. This issue is fixed in version 8.0.6.
How severe is CVE-2026-63447?: CVE-2026-63447 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 none, integrity none, and availability high.
Is CVE-2026-63447 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (48th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-63447?: CVE-2026-63447 affects Oisf Suricata. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-63447?: 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-2026-63447 published?: CVE-2026-63447 was published on 2026-09-18 and last updated on 2026-09-28.

References

Affected products (1)

cpe:2.3:a:oisf:suricata:8.0.5:*:*:*:*:*:*:*

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