Security readout for executives and security teams
Plain-English summary
A flaw in Windows cryptographic processing could let a user who already has local, authorized access alter protected information. Successful exploitation could seriously affect confidentiality and integrity, but the supplied evidence indicates no availability impact. The attacker must already possess low-level privileges on an affected system.
Executive priority
Treat as a high-priority patching issue, especially on shared servers, administrator workstations, and systems exposed to less-trusted local users. It is not evidenced as an active-exploitation emergency, but potential confidentiality and integrity loss warrants prompt remediation within the normal high-severity window.
Technical view
CVE-2026-55144 is a CWE-325 missing cryptographic step vulnerability in Windows CryptoAPI/CNG. The CVSS 3.1 score is 7.1: local access, low complexity, low privileges, and no user interaction. Microsoft identifies high confidentiality and integrity impacts, with no availability impact.
Likely exposure
Exposure is limited to the listed Windows 11 24H2, 25H2, and 26H1 versions, plus Windows Server 2022 and 2025, including Server Core. Risk is greater where local accounts, interactive access, or compromised low-privilege users exist. The bundle does not identify specific vulnerable applications or cryptographic operations.
Exploitation context
The attacker requires authorized local access and low privileges; remote unauthenticated exploitation is not supported by the supplied vector. KEV status is false, and the CVSS exploit-maturity metric is unproven. No supplied source establishes active exploitation or public exploit availability.
Researcher notes
The bundle names CNG in the title but describes Windows CryptoAPI, without identifying the precise function, missing operation, tampering target, or fixed builds. Assessment should therefore remain at the documented boundary. Do not infer remote reachability or broader product impact. Consult Microsoft's advisory for package-level remediation details.
Mitigation direction
- Apply Microsoft's security update for CVE-2026-55144 according to the vendor advisory.
- Prioritize affected systems permitting local logon, shared administration, or access by less-trusted users.
- Restrict unnecessary local accounts and interactive access while remediation is pending.
- Check Microsoft guidance for fixed build numbers and any additional mitigations.
Validation and detection
- Inventory systems against the affected Windows products and versions listed in the CVE record.
- Verify Microsoft's CVE-specific security update is installed using enterprise patch-compliance tooling.
- Confirm remediated build numbers against the current Microsoft advisory; fixed builds are absent from this bundle.
- Review local account access and authentication records for unexpected activity on affected systems.
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-325: 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 lookupCVE-2026-55144 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
- 7.1 (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:N/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:N/E:U/RL:O/RC:C1.85.2microsoftVulnerability scoring details
Base CVSS 3.1 score
7.1HighVector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N/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
- Windows Cryptography API: Next Generation (CNG) Tampering 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.
Missing Cryptographic Step
Missing Cryptographic Step represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.