Security Affairs newsletter Round 543 by Pierluigi Paganini

CVE-2025-10035 is a critical (CVSS 9.8) deserialization-of-untrusted-data flaw (CWE-502) in the License Servlet of Fortra GoAnywhere Managed File Transfer (MFT). It is triggered when the servlet processes a license response carrying a validly forged signature, causing it to deserialize an arbitrary attacker-controlled object; the CVSS vector indicates the attack is network-based and requires no privileges or user interaction. Successful exploitation can lead to command injection (CWE-77), effectively giving an attacker command execution on the MFT server and access to the files and credentials that flow through it. Any organization running GoAnywhere MFT, which is commonly deployed as a central file-transfer hub, is affected, although specific affected/fixed version ranges are not provided in the available data. Exploitation is confirmed in the wild: the flaw was added to CISA's KEV catalog on 2025-09-29 with known ransomware use, Microsoft attributes attacks to the Storm-1175 ransomware affiliate (Medusa, now reportedly replaced by StormEncryptor), and EPSS assigns a 99.8% probability of exploitation within 30 days.

Do: Apply mitigations or patches per Fortra's vendor instructions immediately, as this is a KEV entry carrying BOD 22-01 requirements for federal agencies (patch or discontinue use if mitigations are unavailable). Because a ransomware affiliate (Storm-1175, using Medusa/StormEncryptor) is actively exploiting it, hunt for compromise: review License Servlet traffic and logs for forged license responses, check for unexpected processes or new accounts, and look for signs of lateral movement. Until patched, restrict or remove internet exposure of GoAnywhere MFT admin and license interfaces.

SolarWinds Web Help Desk contains an unauthenticated deserialization of untrusted data vulnerability (CWE-502) in its AjaxProxy component that allows remote attackers to run arbitrary commands on the host machine without any credentials or user interaction. It is triggered by sending a crafted request to the AjaxProxy endpoint of an affected Web Help Desk installation. Successful exploitation yields full code execution on the server, and the flaw is known to be used in ransomware campaigns. Any organization running SolarWinds Web Help Desk is affected, including installations already patched for the earlier CVE-2024-28988 and CVE-2024-28986, since this flaw is a patch bypass of both. The flaw carries a very high exploitation probability (EPSS ~89.5%) and was added to CISA's Known Exploited Vulnerabilities catalog on 2026-03-09 with known ransomware use.

Do: Immediately apply SolarWinds' hotfix for CVE-2025-26399 per the vendor's instructions — organizations that previously patched CVE-2024-28988 or CVE-2024-28986 must apply the new hotfix because those patches do not close this flaw. If the hotfix cannot be applied right away, restrict network access to Web Help Desk (firewall/VPN, limit exposure of the service to the internet) and discontinue use if mitigations are unavailable, per CISA KEV/BOD 22-01 guidance. Given known ransomware use, review Web Help Desk hosts for signs of compromise, including unexpected process execution and accounts or data accessed via the server.

Heap-based buffer overflow in Kernel Streaming WOW Thunk Service Driver allows an authorized attacker to elevate privileges locally.