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SolarWinds fixes critical Web Help Desk RCE vulnerabilities, upgrade ASAP!

Vulnerabilities mentionedAll →

CVEVulnerabilityCVSSEPSSFlagsAffectedExposurePublished
CVE-2024-28986
Java Deserialization RCE in SolarWinds Web Help Desk

SolarWinds Web Help Desk is susceptible to a Java deserialization of untrusted data flaw (CWE-502) in which maliciously crafted serialized Java data sent to the application can trigger remote code execution on the host machine. The flaw is rated 9.8 (network vector, no privileges or user interaction required), though SolarWinds has been unable to reproduce exploitation without authentication after thorough testing and recommends patching all deployments out of caution. A successful attacker gains the ability to run arbitrary commands on the Web Help Desk server, typically yielding control of the host and access to help-desk data. All Web Help Desk versions are potentially affected, and SolarWinds has released a hotfix/patch to address the issue. The bug is being actively exploited: CISA added it to the Known Exploited Vulnerabilities catalog on 2024-08-15, ordered federal agencies to patch by a Friday deadline, and EPSS estimates an 84.6% probability of exploitation within 30 days (100th percentile).

Do: Upgrade every Web Help Desk deployment to the patched release per SolarWinds' security advisory (a hotfix addressing the issue in all versions is available); if immediate patching is not possible, restrict network access to the Web Help Desk web interface and watch the host for signs of command execution. Federal agencies must meet the CISA KEV remediation deadline, and defenders should also review SolarWinds' related Web Help Desk advisories (including the separately fixed hardcoded-credential issue) while patching.

9.885% KEV
  • SolarWinds Web Help Desk all versions prior to the vendor hotfix/patch (SolarWinds stated the critical RCE affected all Web Help Desk versions; upgrade to the latest patched release per
moderateplausibly on the order of tens of thousands of on-premises deployments, with internet-exposed instances likely numbering in the low thousands
CVE-2024-28987
Hardcoded Credential in SolarWinds Web Help Desk Allows Unauthenticated Access

SolarWinds Web Help Desk (WHD) contains hard-coded credentials (CWE-798): fixed, built-in authentication material embedded in the shipped software. Because the same credentials exist on every WHD installation, a remote attacker who knows them can authenticate to WHD without any user account, with no privileges or user interaction required (CVSS 3.1 9.1, AV:N/AC:L/PR:N/UI:N). Successful use grants access to internal WHD functionality and the ability to modify data, with high confidentiality and integrity impact but no availability impact. Any organization running an unpatched WHD instance is affected, particularly internet-exposed deployments such as those operated by managed service providers and enterprise IT service desks. The flaw is being actively exploited in the wild: CISA added it to the Known Exploited Vulnerabilities catalog on 2024-10-15 (ransomware use not yet reported), EPSS assigns a 93.2% probability of exploitation within 30 days (100th percentile), and no public proof-of-concept was known at the time of this record.

Do: Upgrade all WHD instances to the patched SolarWinds release that includes the October 2024 fix for CVE-2024-28987 (check the SolarWinds PSIRT advisory for the exact fixed version, e.g., WHD 12.8.4 or later); the required KEV action applies, and U.S. federal agencies must remediate by November 5, 2024. Prioritize internet-exposed WHD servers: restrict network access to the help desk interface/API until patched and review logs for unauthenticated access using built-in credentials, since exploitation is confirmed in the wild. If patching is not possible, apply mitigations per vendor instructions or discontinue use of the product, as CISA recommends.

9.193% KEV
  • SolarWinds Web Help Desk (WHD) unpatched WHD releases at the time of disclosure (CISA lists the affected product as SolarWinds Web Help Desk; no version range is provided in this data — see t
moderate≈ a few thousand internet-exposed WHD instances, with total deployments likely in the low tens of thousands worldwide (estimate)
CVE-2025-40551
Unauthenticated Deserialization RCE in SolarWinds Web Help Desk

SolarWinds Web Help Desk contains a deserialization of untrusted data flaw (CWE-502) that allows an unauthenticated attacker to reach the vulnerable functionality over the network and have it deserialize attacker-supplied input. By sending crafted serialized data, the attacker triggers remote code execution and can run arbitrary commands on the host machine running Web Help Desk. Successful compromise grants control of the help desk server, and observed intrusions include attackers installing Zoho agents and Velociraptor for post-exploitation. Any organization running the product is affected, particularly instances exposed to the internet; the flaw carries a CVSS 9.8 (critical) score and federal agencies are under a CISA (BOD 22-01) patching deadline. The vulnerability is being actively exploited in the wild and was added to the CISA KEV catalog on 2026-02-03, with an EPSS probability of 83.6% that it will be exploited within 30 days.

Do: Upgrade Web Help Desk to the latest patched release per the SolarWinds security advisory (the source data does not specify a fixed version number), and follow BOD 22-01 mitigations or discontinue use if mitigation is not possible, noting the federal patching deadline. Until patched, restrict internet-facing access to the Web Help Desk server. Check hosts for post-exploitation artifacts reported in the wild, such as unexpected Zoho agent installations and Velociraptor, and review logs for unauthenticated requests targeting the application.

9.8
group max
84% KEV
  • SolarWinds Web Help Desk
large≈ tens of thousands of on-premises deployments worldwide (order of magnitude: 10,000–100,000 systems), an estimate
Full article433 words · extracted from helpnetsecurity.com · click to collapse

SolarWinds has fixed six critical and high-severity vulnerabilities in its popular Web Help Desk (WHD) support ticketing and asset management solution, and is urging customers to upgrade to v2026.1 as soon as possible.

SolarWinds Web Help Desk vulnerabilities

The vulnerabilities

The WHD vulnerabilities fixed were unearthed by Jimi Sebree from Horizon3.ai and Piotr Bazydlo from watchTowr.

Sebree flagged a security control bypass flaw (CVE-2025-40536), hardcoded/static credentials (CVE-2025-40537), and an untrusted data deserialization vulnerability (CVE-2025-40551).

While the first two may allow unauthenticated attackers to gain access to restricted functionality or administrative functions, CVE-2025-40551 may allow them to achieve remote code execution and execute payloads and commands on the host machine. (More often than not, WHD is deployed on on-premise company servers.)

Following the release of the fixes, Sebree shared technical details about these vulnerabilities, loosely outlined how they can be exploited, and gave a quick rundown on indicators of compromise that might show up in WHD logs after successful exploitation attempts.

Bazydlo discovered two authentication bypass flaws (CVE-2025-40552 and CVE-2025-40554) and an untrusted data deserialization vulnerability (CVE-2025-40553). All three are deemed critical by SolarWinds.

No in-the-wild exploitation detected (for now)

The vulnerabilities affect SolarWinds Web Help Desk versions 12.8.8 Hotfix 1 and below and have been fixed in v2026.1.

There is currently no indication of any of them being actively exploited, but that state of affairs may soon change.

WHD is an IT help desk solution used by many organizations, small and medium-size businesses, and managed service providers around the world.

In 2024, SolarWinds fixed two vulnerabilities – CVE-2024-28986 and CVE-2024-28987 – that were picked up and leveraged by attackers within days and months of their disclosure.

UPDATE (February 2, 2026, 05:40 a.m. ET):

Though it’s efficacy is yet to be validated, proof-of-concept code for CVE-2025-40554 has apparently been made public, the Dutch National Cyber Security Center (NCSC NL) shared.

“No large-scale abuse has yet to be observed, but the NCSC expects an increase in scanning and abuse traffic, especially in systems that are publicly accessible,” they added.

UPDATE (February 3, 2026, 03:35 p.m. ET):

The US Cybersecurity and Infrastructure Security Agency (CISA) added CVE-2025-40551 to its Known Exploited Vulnerabilities catalog.

UPDATE (February 13, 2026, 08:55 a.m. ET):

Microsoft and Huntress shared details about the recent attacks they observed on Web Help Desk instances, though they were unable to tell which particular vulnerability (or vulnerabilities) the attackers exploited.

CISA added CVE-2025-40536 to the Known Exploited Vulnerabilities catalog.

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Text extracted automatically; images, tables and formatting may be missing. Original: https://www.helpnetsecurity.com/2026/01/29/solarwinds-web-help-desk-rce-vulnerabilities/