CVE-2026-48558
SimpleHelp Authentication Bypass Vulnerability - [Actively Exploited]
Description
SimpleHelp versions 5.5.15 and prior and 6.0 pre-release versions contain an authentication bypass vulnerability in the OIDC authentication flow. When OIDC authentication is configured, identity tokens submitted during login are accepted without verifying their cryptographic signature. In a vulnerable configuration, a remote, unauthenticated attacker can submit a forged token containing arbitrary identity claims to obtain a fully authenticated technician session. In some configurations, this may also allow bypass of multi-factor authentication. No user interaction is required.
INFO
Published Date :
June 12, 2026, 6:16 p.m.
Last Modified :
June 30, 2026, 1:03 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CISA KEV (Known Exploited Vulnerabilities)
For the benefit of the cybersecurity community and network defenders—and to help every organization better manage vulnerabilities and keep pace with threat activity—CISA maintains the authoritative source of vulnerabilities that have been exploited in the wild.
SimpleHelp contains an authentication bypass vulnerability in the OIDC authentication flow. When OIDC authentication is configured, identity tokens submitted during login are accepted without verifying their cryptographic signature. In a vulnerable configuration, a remote, unauthenticated attacker can submit a forged token containing arbitrary identity claims to obtain a fully authenticated technician session. In some configurations, this may also allow bypass of multi-factor authentication.
Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
Unknown
https://simple-help.com/security/simplehelp-security-update-2026-05 ; BOD 26-04: https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk ; Forensics Triage Requirements: https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk ; https://nvd.nist.gov/vuln/detail/CVE-2026-48558
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | CRITICAL | 83251b91-4cc7-4094-a5c7-464a1b83ea10 | ||||
| CVSS 3.1 | CRITICAL | [email protected] | ||||
| CVSS 3.1 | CRITICAL | MITRE-CVE | ||||
| CVSS 4.0 | CRITICAL | 83251b91-4cc7-4094-a5c7-464a1b83ea10 | ||||
| CVSS 4.0 | CRITICAL | [email protected] |
Solution
- Update to a non-vulnerable version of SimpleHelp.
- Ensure OIDC authentication is securely configured.
- Verify identity token signature validation.
Public PoC/Exploit Available at Github
CVE-2026-48558 has a 4 public
PoC/Exploit available at Github.
Go to the Public Exploits tab to see the list.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-48558.
| URL | Resource |
|---|---|
| https://horizon3.ai/attack-research/disclosures/cve-2026-48558-simplehelp-authentication-bypass-iocs/ | Third Party Advisory |
| https://simple-help.com/release-news | Release Notes |
| https://simple-help.com/security/simplehelp-security-update-2026-05 | Patch Vendor Advisory |
| https://blackpointcyber.com/blog/a-djinn-in-the-machine-taskweavers-node-js-intrusion-chain/ | Technical Description Third Party Advisory |
| https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-48558 | US Government Resource |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-48558 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-48558
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
SimpleHelp OIDC Authentication Bypass PoC
Python
None
Python CLI tool to check CVE details + nuclei template coverage. Security research writeups in /research.
Python
Reports that I gather from research over time for different purposes.
YARA
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-48558 vulnerability anywhere in the article.
-
security.nl
Nederlandse SimpleHelp RMM-servers bevatten actief misbruikt lek
Wereldwijd zijn nog honderden SimpleHelp RMM-servers te vinden die een actief misbruikte kwetsbaarheid bevatten, waaronder achttien in Nederland. Dat laat The Shadowserver Foundation op basis van eige ... Read more
-
TheCyberThrone
CISA Adds CVE-2026-45659 SharePoint Vulnerability to KEV
The U.S. Cybersecurity and Infrastructure Security Agency (Cybersecurity and Infrastructure Security Agency) has added a critical Microsoft SharePoint vulnerability to its Known Exploited Vulnerabilit ... Read more
-
TheCyberThrone
Google Chrome 150 Security Update: 382 Vulnerabilities Fixed
Google has released Chrome 150, delivering one of its most extensive security patch cycles of 2026. The update addresses 382 vulnerabilities, including 15 critical flaws, reinforcing a pattern the sec ... Read more
-
TheCyberThrone
CVE-2026-48558: SimpleHelp OIDC Flaw Added to KEV
Authentication systems are built on trust.But when that trust is broken at the protocol layer, the entire security model collapses.That is exactly what happened with CVE-2026-48558, a critical vulnera ... Read more
-
security.nl
Gevaarlijk lek in SimpleHelp RMM-servers actief misbruikt bij aanvallen
Een gevaarlijke kwetsbaarheid in SimpleHelp RMM-servers wordt actief misbruikt bij aanvallen en kan grote gevolgen voor allerlei organisaties hebben, zo waarschuwt het Amerikaanse cyberagentschap CISA ... Read more
-
The Hacker News
Attackers Exploit SimpleHelp CVE-2026-48558 to Deploy TaskWeaver and Djinn Stealer
An unknown threat actor has been observed exploiting a recently disclosed maximum-severity security flaw in SimpleHelp to deliver two previously unreported malware families, TaskWeaver and Djinn Steal ... Read more
The following table lists the changes that have been made to the
CVE-2026-48558 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
Jun. 30, 2026
Action Type Old Value New Value Added CPE Configuration OR *cpe:2.3:a:simple-help:simplehelp:*:*:*:*:*:*:*:* versions up to (excluding) 5.5.16 *cpe:2.3:a:simple-help:simplehelp:6.0:pre-release:*:*:*:*:*:* Added Reference Type VulnCheck: https://horizon3.ai/attack-research/disclosures/cve-2026-48558-simplehelp-authentication-bypass-iocs/ Types: Third Party Advisory Added Reference Type VulnCheck: https://simple-help.com/release-news Types: Release Notes Added Reference Type VulnCheck: https://simple-help.com/security/simplehelp-security-update-2026-05 Types: Patch, Vendor Advisory Added Reference Type CISA-ADP: https://blackpointcyber.com/blog/a-djinn-in-the-machine-taskweavers-node-js-intrusion-chain/ Types: Technical Description, Third Party Advisory Added Reference Type CISA-ADP: https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-48558 Types: US Government Resource -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 30, 2026
Action Type Old Value New Value Changed SSVC {'id': 'CVE-2026-48558', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'active'}, {'automatable': 'yes'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-06-29T20:01:08.460450Z'} {'id': 'CVE-2026-48558', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'active'}, {'automatable': 'yes'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-06-12T00:00:00+00:00'} -
CVE CISA KEV Update by 9119a7d8-5eab-497f-8521-727c672e3725
Jun. 29, 2026
Action Type Old Value New Value Added Date Added 2026-06-29 Added Due Date 2026-06-29 Added Required Action 2026-06-29 Added Vulnerability Name 2026-06-29 -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 29, 2026
Action Type Old Value New Value Added Reference https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-48558 Changed SSVC {'id': 'CVE-2026-48558', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'yes'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-06-13T03:56:10.774456Z'} {'id': 'CVE-2026-48558', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'active'}, {'automatable': 'yes'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-06-29T20:01:08.460450Z'} -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 29, 2026
Action Type Old Value New Value Added Reference https://blackpointcyber.com/blog/a-djinn-in-the-machine-taskweavers-node-js-intrusion-chain/ Changed SSVC {'id': 'CVE-2026-48558', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'yes'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-06-12T00:00:00+00:00'} {'id': 'CVE-2026-48558', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'yes'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-06-13T03:56:10.774456Z'} -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 17, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-48558', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'yes'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-06-12T00:00:00+00:00'} -
CVE Modified by [email protected]
Jun. 17, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'SimpleHelp', 'product': 'SimpleHelp', 'versions': [{'status': 'affected', 'version': '5.5.0', 'lessThan': '5.5.16', 'versionType': 'semver'}, {'status': 'affected', 'version': '6.0', 'lessThan': '6.0 RC2', 'versionType': 'custom'}], 'defaultStatus': 'affected'}] -
New CVE Received by [email protected]
Jun. 12, 2026
Action Type Old Value New Value Added Description SimpleHelp versions 5.5.15 and prior and 6.0 pre-release versions contain an authentication bypass vulnerability in the OIDC authentication flow. When OIDC authentication is configured, identity tokens submitted during login are accepted without verifying their cryptographic signature. In a vulnerable configuration, a remote, unauthenticated attacker can submit a forged token containing arbitrary identity claims to obtain a fully authenticated technician session. In some configurations, this may also allow bypass of multi-factor authentication. No user interaction is required. Added CVSS V4.0 AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H Added CWE CWE-347 Added Reference https://horizon3.ai/attack-research/disclosures/cve-2026-48558-simplehelp-authentication-bypass-iocs/ Added Reference https://simple-help.com/release-news Added Reference https://simple-help.com/security/simplehelp-security-update-2026-05