How severe is CVE-2026-55944?

CVE-2026-55944 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-2026-55944 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-55944?

CVE-2026-55944 affects Microsoft Dynamics Nav. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-55944?

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-2026-55944 published?

CVE-2026-55944 was published on 2026-07-14 and last updated on 2026-07-22.

CVE-2026-55944

CVE-2026-55944 is a critical-severity vulnerability in Microsoft Dynamics Nav 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-502.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 1% (68th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-502
Affected product: Microsoft Dynamics Nav
Published: 2026-07-14
Last modified: 2026-07-22

Description

Deserialization of untrusted data in Microsoft Dynamics NAV allows an unauthorized attacker to execute code over a network.

Frequently asked questions

What is CVE-2026-55944?: Deserialization of untrusted data in Microsoft Dynamics NAV allows an unauthorized attacker to execute code over a network.
How severe is CVE-2026-55944?: CVE-2026-55944 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-2026-55944 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-55944?: CVE-2026-55944 affects Microsoft Dynamics Nav. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-55944?: 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-2026-55944 published?: CVE-2026-55944 was published on 2026-07-14 and last updated on 2026-07-22.

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55944

Affected products (1)

cpe:2.3:a:microsoft:dynamics_nav:2018:*:*:*:*:*:*:*

More vulnerabilities in Microsoft Dynamics Nav

CVE-2022-41127 — High (CVSS 8.5): Microsoft Dynamics NAV and Microsoft Dynamics 365 Business Central (On Premises) Remote Code Execution Vulnerability
CVE-2020-1022 — High (CVSS 8.0): A remote code execution vulnerability exists in Microsoft Dynamics Business Central, aka 'Dynamics Business Central…
CVE-2020-0905 — High (CVSS 8.0): An remote code execution vulnerability exists in Microsoft Dynamics Business Central, aka 'Dynamics Business Central…
CVE-2020-1018 — High (CVSS 7.5): An information disclosure vulnerability exists when Microsoft Dynamics Business Central/NAV on-premise does not…
CVE-2020-17133 — Medium (CVSS 6.5): Microsoft Dynamics Business Central/NAV Information Disclosure Vulnerability
CVE-2021-1724 — Medium (CVSS 6.1): Microsoft Dynamics Business Central Cross-site Scripting Vulnerability

All CVEs affecting Microsoft Dynamics Nav →

Other CWE-502 (Deserialization of Untrusted Data) vulnerabilities

CVE-2026-69836 — Critical (CVSS 10.0): Deserialization of untrusted data in Microsoft Entra ID allows an unauthorized attacker to execute code over a network.
CVE-2026-17061 — Critical (CVSS 10.0): A Deserialization of Untrusted Data vulnerability affecting SIMULIA Execution Engine from Release 2023 through Release…
CVE-2026-11756 — Critical (CVSS 10.0): A Deserialization of Untrusted Data vulnerability affecting Station Launcher App in 3DEXPERIENCE platform from Release…
CVE-2026-41104 — Critical (CVSS 10.0): Deserialization of untrusted data in Microsoft Planetary Computer Pro allows an unauthorized attacker to disclose…
CVE-2026-43633 — Critical (CVSS 10.0): HestiaCP versions 1.9.0 through 1.9.4 contain a deserialization vulnerability in the web terminal component caused by a…
CVE-2026-33819 — Critical (CVSS 10.0): Deserialization of untrusted data in Microsoft Bing allows an unauthorized attacker to execute code over a network.

Browse all CWE-502 (Deserialization of Untrusted Data) vulnerabilities →