Security readout for executives and security teams
Plain-English summary
CVE-2026-26117 is a high-severity local privilege escalation issue in Microsoft Arc Enabled Servers' Azure Connected Machine Agent. A low-privileged authorized attacker on an affected host could bypass authentication through an alternate path or channel and gain higher privileges.
Executive priority
Treat this as a priority patching item for Arc-managed Windows server fleets. It is not cited as exploited, but successful abuse could provide full host compromise after local access.
Technical view
The source bundle describes CWE-288 authentication bypass in Azure Connected Machine Agent, affecting version 1.0.0. CVSS 3.1 is 7.8 with local attack vector, low complexity, low privileges required, no user interaction, unchanged scope, and high confidentiality, integrity, and availability impact.
Likely exposure
Exposure appears limited to organizations running Arc Enabled Servers with Azure Connected Machine Agent version 1.0.0. The provided sources do not identify additional affected versions, platforms, or downstream products.
Exploitation context
The bundle does not report active exploitation, and KEV status is false. Exploitation requires authorized local access, but no user interaction, making shared systems and hosts with broad local access more concerning.
Researcher notes
Evidence is sparse beyond the CVE and MSRC metadata. The key confirmed traits are CWE-288, local privilege escalation, low complexity, low privileges required, official fix available, and no KEV listing in the supplied bundle.
Mitigation direction
- Apply the Microsoft-provided update or remediation from the MSRC advisory.
- Inventory Arc-enabled servers and identify Azure Connected Machine Agent version 1.0.0.
- Prioritize remediation on internet-administered, shared, or high-value Windows servers.
- Limit local interactive access to affected hosts until remediated.
- Monitor Microsoft guidance for revised affected-version or mitigation details.
Validation and detection
- Confirm whether Azure Connected Machine Agent version 1.0.0 is installed.
- Verify the relevant Microsoft update or fixed agent version is applied.
- Check asset inventory for unmanaged Arc-enabled servers.
- Review local user and administrator group membership on affected hosts.
- Document exceptions and compensating access controls for delayed remediation.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-288: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCredential and access behavior lookup
The CVE wording references authentication or credential exposure, so valid-account and credential-access review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupPrivilege behavior lookup
The CVE wording references privilege impact, so privilege escalation and authorization behavior review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2026-26117 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- High
- CVSS
- 7.8 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
SSVC decision data
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C1.85.9microsoftVulnerability scoring details
Base CVSS 3.1 score
7.8HighVector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- Arc Enabled Servers - Azure Connected Machine Agent Elevation of Privilege VulnerabilityCVE reference, microsoft · vendor-advisory, patch
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Authentication Bypass Using an Alternate Path or Channel
Authentication Bypass Using an Alternate Path or Channel represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.