How severe is CVE-2023-26463?

CVE-2023-26463 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2023-26463 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (81st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-26463?

CVE-2023-26463 primarily affects Strongswan. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-26463?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2023-26463 published?

CVE-2023-26463 was published on 2023-04-15 and last updated on 2026-06-17.

CVE-2023-26463

CVE-2023-26463 is a critical-severity vulnerability in Strongswan with a CVSS 3.x base score of 9.8. 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-295.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 2% (81st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-295
Affected product: Strongswan
Published: 2023-04-15
Last modified: 2026-06-17

Description

strongSwan 5.9.8 and 5.9.9 potentially allows remote code execution because it uses a variable named "public" for two different purposes within the same function. There is initially incorrect access control, later followed by an expired pointer dereference. One attack vector is sending an untrusted client certificate during EAP-TLS. A server is affected only if it loads plugins that implement TLS-based EAP methods (EAP-TLS, EAP-TTLS, EAP-PEAP, or EAP-TNC). This is fixed in 5.9.10.

Frequently asked questions

What is CVE-2023-26463?: strongSwan 5.9.8 and 5.9.9 potentially allows remote code execution because it uses a variable named "public" for two different purposes within the same function. There is initially incorrect access control, later followed by an expired pointer dereference. One attack vector is sending an untrusted client certificate during EAP-TLS. A server is affected only if it loads plugins that implement TLS-based EAP methods (EAP-TLS, EAP-TTLS, EAP-PEAP, or EAP-TNC). This is fixed in 5.9.10.
How severe is CVE-2023-26463?: CVE-2023-26463 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2023-26463 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (81st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-26463?: CVE-2023-26463 primarily affects Strongswan. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-26463?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2023-26463 published?: CVE-2023-26463 was published on 2023-04-15 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:strongswan:strongswan:5.9.8:-:*:*:*:*:*:*
cpe:2.3:a:strongswan:strongswan:5.9.9:-:*:*:*:*:*:*

More vulnerabilities in Strongswan

CVE-2004-0590 — Critical (CVSS 10.0): FreeS/WAN 1.x and 2.x, and other related products including superfreeswan 1.x, openswan 1.x before 1.0.6, openswan 2.x…
CVE-2023-41913 — Critical (CVSS 9.8): strongSwan before 5.9.12 has a buffer overflow and possible unauthenticated remote code execution via a DH public value…
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