How severe is CVE-2023-30312?

CVE-2023-30312 has a CVSS 3.x base score of 7.3, rated high severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity high, and availability high.

Is CVE-2023-30312 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (21st percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2023-30312?

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-2023-30312 have an EU (EUVD) identifier?

Yes. CVE-2023-30312 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-34735.

When was CVE-2023-30312 published?

CVE-2023-30312 was published on 2024-05-28 and last updated on 2026-06-17.

CVE-2023-30312

CVE-2023-30312 is a high-severity vulnerability with a CVSS 3.x base score of 7.3. 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-203.

Key facts

Severity: High (CVSS 3.x base score 7.3)
EPSS exploit prediction: 0% (21st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2023-34735
Weakness: CWE-203
Published: 2024-05-28
Last modified: 2026-06-17

Description

An issue discovered in OpenWrt 18.06, 19.07, 21.02, 22.03, and beyond allows off-path attackers to hijack TCP sessions, which could lead to a denial of service, impersonating the client to the server (e.g., for access to files over FTP), and impersonating the server to the client (e.g., to deliver false information from a finance website). This occurs because nf_conntrack_tcp_no_window_check is true by default.

Frequently asked questions

What is CVE-2023-30312?: An issue discovered in OpenWrt 18.06, 19.07, 21.02, 22.03, and beyond allows off-path attackers to hijack TCP sessions, which could lead to a denial of service, impersonating the client to the server (e.g., for access to files over FTP), and impersonating the server to the client (e.g., to deliver false information from a finance website). This occurs because nf_conntrack_tcp_no_window_check is true by default.
How severe is CVE-2023-30312?: CVE-2023-30312 has a CVSS 3.x base score of 7.3, rated high severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity high, and availability high.
Is CVE-2023-30312 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (21st percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2023-30312?: 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-2023-30312 have an EU (EUVD) identifier?: Yes. CVE-2023-30312 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-34735.
When was CVE-2023-30312 published?: CVE-2023-30312 was published on 2024-05-28 and last updated on 2026-06-17.

References

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