CVE-2021-35063
CVE-2021-35063 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.
Key facts
- Severity: High (CVSS 3.x base score 7.5)
- CVSS v2: 5.0
- EPSS exploit prediction: 2% (78th percentile)
- Actively exploited: Not listed in CISA KEV
- Affected product: Oisf Suricata
- Published:
- Last modified:
Description
Suricata before 5.0.7 and 6.x before 6.0.3 has a "critical evasion."
Frequently asked questions
- What is CVE-2021-35063?
- Suricata before 5.0.7 and 6.x before 6.0.3 has a "critical evasion."
- How severe is CVE-2021-35063?
- CVE-2021-35063 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-2021-35063 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-35063?
- CVE-2021-35063 primarily affects Oisf Suricata. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2021-35063?
- 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-2021-35063 published?
- CVE-2021-35063 was published on 2021-07-22 and last updated on 2026-06-17.
References
- https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=990835
- https://bugzilla.redhat.com/show_bug.cgi?id=1980453
- https://forum.suricata.io/t/suricata-6-0-3-and-5-0-7-released/1489
- https://github.com/OISF/suricata/releases
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JU27J2ZYG6FBDL5CERE6FBB4ZFGHOROE/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XEP7PWY4LRT2R4MFLV7JIJRYZEZ7RQFL/
- https://security-tracker.debian.org/tracker/CVE-2021-35063
Affected products (5)
- cpe:2.3:a:oisf:suricata:*:*:*:*:*:*:*:*
- cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
- cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
- cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*
- cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*
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