CVE-2026-126768: CVE-2026-126768: OpsTree REMS through 1.0.0 contains an authentication bypass vulnerability that allows una…
Unknown · OpsTree REMS · NVD published 2026-11-12 · posted 2026-11-11 · last modified 2026-11-12
CVE-2026-126768 at a glance
CVE-2026-126768 is a critical-severity Auth Bypass vulnerability in OpsTree REMS, with a CVSS 4.0 base score of 9.3. NVD published it on 2026-11-12 and classifies the weakness as CWE-287. NVD does not list a fixed version, so the vendor advisory is the reference for the fix. CVERadar maps 2 MITRE ATT&CK techniques across Initial Access, Stealth, Persistence and Privilege Escalation, inferred from the CWE and the description. Its CVERadar threat level is 47/100.
What it is
OpsTree REMS through 1.0.0 contains an authentication bypass vulnerability that allows unauthenticated attackers to obtain valid JWTs by setting the client-controlled is_local_auth field. Attackers can send a POST /api/v1/user/login/ request for the admin account with an invalid password and is_local_auth true to gain SuperUser administrative access.
| Weakness | CWE-287 definition |
|---|---|
| CVSS vector | CVSS: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/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X (source: VulnCheck) |
| ATT&CK tactics | Initial Access → Persistence → Privilege Escalation → Stealth |
Defend the Chain
The attack chain for CVE-2026-126768 laid across the MITRE ATT&CK Enterprise tactics. Solid cards come from the MITRE CTID KEV mappings; dashed cards are inferred by CVERadar from the CWE or description. Correct defences are real ATT&CK mitigations for that technique.
Pick a red technique card on the board, then choose the defence that stops it.
Defend against T1190 Exploit Public-Facing Application Inferred
Inferred from CWE CWE-287
Patches, mitigations and detection
Fixed versions
NVD does not list a fixed version for this CVE. Use the vendor advisory below.
Derived from the NVD CPE configuration (versionEndExcluding / versionEndIncluding). Always confirm with the vendor advisory.
Vendor advisories and patches
No vendor-tagged reference yet; see the full reference list.
MITRE ATT&CK mitigations for this chain
- M1048 Application Isolation and Sandboxing (for T1190) : Application isolation will limit what other processes and system features the exploited target can access.
- M1037 Filter Network Traffic (for T1190) : Restrict outbound network traffic from public-facing servers to prevent unauthorized connections from initiating communications with attacker-controlled infrastructure. While this may not prevent the initial exploitation, it limits the attacker's ability to verify and control the compromised server post-exploit, reduci
- M1030 Network Segmentation (for T1190) : Segment externally facing servers and services from the rest of the network with a DMZ or on separate hosting infrastructure.
- M1016 Vulnerability Scanning (for T1190) : Regularly scan externally facing systems for vulnerabilities and establish procedures to rapidly patch systems when critical vulnerabilities are discovered through scanning and through public disclosure.
- M1026 Privileged Account Management (for T1190, T1078) : Use least privilege for service accounts will limit what permissions the exploited process gets on the rest of the system.
- M1050 Exploit Protection (for T1190) : Web Application Firewalls may be used to limit exposure of applications to prevent exploit traffic from reaching the application.
- M1035 Limit Access to Resource Over Network (for T1190) : Ensure that all publicly exposed services are actually intended to be so, and restrict access to any that should only be available internally.
- M1051 Update Software (for T1190) : Update software regularly by employing patch management for externally exposed applications.
- M1027 Password Policies (for T1078) : Applications and appliances that utilize default username and password should be changed immediately after the installation, and before deployment to a production environment. When possible, applications that use SSH keys should be updated periodically and properly secured. Policies should minimize (if not eliminate)
- M1018 User Account Management (for T1078) : Regularly audit user accounts for activity and deactivate or remove any that are no longer needed.
Detection Generic guidance
- Initial Access: Alert on unusual requests to the affected service (odd paths, oversized payloads, exploit strings) in WAF, reverse-proxy and application logs.
- Persistence: Look for new files in web roots, new scheduled tasks/services, and new accounts created after the exposure window.
- Privilege Escalation: Alert on processes gaining SYSTEM/root unexpectedly, and on exploitation crashes of privileged services.
Response checklist Generic guidance
- Inventory: find every instance of the affected product and version (include internet-facing and forgotten ones).
- Patch or mitigate per the vendor advisory; if you cannot patch, remove internet exposure or apply the vendor workaround.
- Assume compromise if the system was exposed before patching: hunt for the indicators in the advisory and review logs back to the disclosure date.
- Rotate credentials and secrets stored on or used by the affected system if compromise cannot be ruled out.
Sources
- NVD: CVE-2026-126768
- CVE.org record for CVE-2026-126768
- FIRST EPSS score for CVE-2026-126768 (n/a)
- GitHub reference (gist.github.com) gist.github.com/neelkotnis/4676fe10859d84900025cf52188dae46
- Reference (opstree.com) opstree.com/rems-ai-powered-observability/
- VulnCheck reference (vulncheck.com) vulncheck.com/advisories/opstree-rems-through-1.0.0-authentication-bypass-via-is