SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2026-26335

An attacker who obtains these keys can craft a valid ASP.NET ViewState payload that passes integrity validation and is accepted by the application, resulting in server-side deserialization and remote code execution in the context of the IIS application.

CRITICAL 9.3EPSS 2.92%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (2.92%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

Calero VeraSMART versions prior to 2022 R1 use static ASP.NET/IIS machineKey values configured for the VeraSMART web application and stored in C:\\Program Files (x86)\\Veramark\\VeraSMART\\WebRoot\\web.config. An attacker who obtains these keys can craft a valid ASP.NET ViewState payload that passes integrity validation and is accepted by the application, resulting in server-side deserialization and remote code execution in the context of the IIS application.

CVSS 4.0
9.3 CRITICALCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS
2.92% probability · 86th percentile
CISA KEV
Not listed
Weakness
CWE-321
Affected
calero/verasmart
Source
disclosure@vulncheck.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.