How severe is CVE-2023-43826?

CVE-2023-43826 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2023-43826 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (55th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-43826?

CVE-2023-43826 affects Apache Guacamole. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-43826?

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-2023-43826 published?

CVE-2023-43826 was published on 2023-12-19 and last updated on 2026-06-17.

CVE-2023-43826

CVE-2023-43826 is a high-severity vulnerability in Apache Guacamole 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-190.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (55th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-190
Affected product: Apache Guacamole
Published: 2023-12-19
Last modified: 2026-06-17

Description

Apache Guacamole 1.5.3 and older do not consistently ensure that values received from a VNC server will not result in integer overflow. If a user connects to a malicious or compromised VNC server, specially-crafted data could result in memory corruption, possibly allowing arbitrary code to be executed with the privileges of the running guacd process. Users are recommended to upgrade to version 1.5.4, which fixes this issue.

Frequently asked questions

What is CVE-2023-43826?: Apache Guacamole 1.5.3 and older do not consistently ensure that values received from a VNC server will not result in integer overflow. If a user connects to a malicious or compromised VNC server, specially-crafted data could result in memory corruption, possibly allowing arbitrary code to be executed with the privileges of the running guacd process. Users are recommended to upgrade to version 1.5.4, which fixes this issue.
How severe is CVE-2023-43826?: CVE-2023-43826 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2023-43826 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (55th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-43826?: CVE-2023-43826 affects Apache Guacamole. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-43826?: 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-2023-43826 published?: CVE-2023-43826 was published on 2023-12-19 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:apache:guacamole:*:*:*:*:*:*:*:*

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