How severe is CVE-2026-55142?

CVE-2026-55142 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2026-55142 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (48th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-55142?

CVE-2026-55142 primarily affects Microsoft 365 Apps. In total, 14 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-55142?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2026-55142 published?

CVE-2026-55142 was published on 2026-07-14 and last updated on 2026-07-16.

CVE-2026-55142

CVE-2026-55142 is a medium-severity vulnerability in Microsoft 365 Apps with a CVSS 3.x base score of 5.5. 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-197.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
EPSS exploit prediction: 1% (48th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-197
Affected product: Microsoft 365 Apps
Published: 2026-07-14
Last modified: 2026-07-16

Description

Numeric truncation error in Microsoft Office Word allows an unauthorized attacker to disclose information locally.

Frequently asked questions

What is CVE-2026-55142?: Numeric truncation error in Microsoft Office Word allows an unauthorized attacker to disclose information locally.
How severe is CVE-2026-55142?: CVE-2026-55142 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2026-55142 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (48th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-55142?: CVE-2026-55142 primarily affects Microsoft 365 Apps. In total, 14 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-55142?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2026-55142 published?: CVE-2026-55142 was published on 2026-07-14 and last updated on 2026-07-16.

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55142

Affected products (14)

cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:x64:*
cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:x86:*
cpe:2.3:a:microsoft:microsoft_365:-:*:*:*:*:macos:*:*
cpe:2.3:a:microsoft:office_2019:-:*:*:*:*:*:x64:*
cpe:2.3:a:microsoft:office_2019:-:*:*:*:*:*:x86:*
cpe:2.3:a:microsoft:office_2021:-:*:*:*:ltsc:-:x64:*
cpe:2.3:a:microsoft:office_2021:-:*:*:*:ltsc:-:x86:*
cpe:2.3:a:microsoft:office_2024:-:*:*:*:ltsc:-:x64:*
cpe:2.3:a:microsoft:office_2024:-:*:*:*:ltsc:-:x86:*
cpe:2.3:a:microsoft:sharepoint_server:*:*:*:*:subscription:*:*:*
cpe:2.3:a:microsoft:sharepoint_server:2016:*:*:*:enterprise:*:*:*
cpe:2.3:a:microsoft:sharepoint_server:2019:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:word:2016:*:*:*:*:*:x64:*
cpe:2.3:a:microsoft:word:2016:*:*:*:*:*:x86:*

More vulnerabilities in Microsoft 365 Apps

CVE-2026-97749 — Critical (CVSS 9.8): Double free in Microsoft Office Outlook allows an unauthorized attacker to execute code over a network.
CVE-2026-97016 — Critical (CVSS 9.8): Heap-based buffer overflow in Microsoft Office Outlook allows an unauthorized attacker to execute code over a network.
CVE-2026-88178 — Critical (CVSS 9.8): Use after free in Microsoft Office PowerPoint allows an unauthorized attacker to execute code over a network.
CVE-2026-88156 — Critical (CVSS 9.8): Stack-based buffer overflow in Microsoft Office Outlook allows an unauthorized attacker to execute code over a network.
CVE-2026-70300 — Critical (CVSS 9.8): Untrusted pointer dereference in Microsoft Office Word allows an unauthorized attacker to execute code over a network.
CVE-2026-70291 — Critical (CVSS 9.8): Heap-based buffer overflow in Microsoft Office Outlook allows an unauthorized attacker to execute code over a network.

All CVEs affecting Microsoft 365 Apps →

Other CWE-197 vulnerabilities

CVE-2026-115889 — Critical (CVSS 9.9): Wasmtime is a runtime for WebAssembly. Prior to 36.0.19 and 43.0.0, the Cranelift compiler backend bit-packs SSA value…
CVE-2024-43639 — Critical (CVSS 9.8): Windows KDC Proxy Remote Code Execution Vulnerability
CVE-2026-87529 — Critical (CVSS 9.6): Numeric truncation error in Media in Google Chrome prior to 153.0.8010.36 allowed a remote attacker to potentially…
CVE-2020-15202 — Critical (CVSS 9.0): In Tensorflow before versions 1.15.4, 2.0.3, 2.1.2, 2.2.1 and 2.3.1, the `Shard` API in TensorFlow expects the last…
CVE-2024-49018 — High (CVSS 8.8): SQL Server Native Client Remote Code Execution Vulnerability
CVE-2024-43519 — High (CVSS 8.8): Microsoft WDAC OLE DB provider for SQL Server Remote Code Execution Vulnerability

Browse all CWE-197 vulnerabilities →