Security readout for executives and security teams
Plain-English summary
Kiota versions before 1.32.5 can trust naming metadata from an OpenAPI description too much. If a malicious or compromised API description is used to generate a client, it may cause files to be written outside the intended output folder and inject text into generated source declarations.
Executive priority
Treat as urgent for teams using Kiota in automated generation pipelines. The issue can affect source integrity, but risk is concentrated where untrusted API descriptions enter build or developer workflows.
Technical view
The issue affects Microsoft Kiota before 1.32.5. Unsanitized x-ms-kiota-info clientClassName and clientNamespaceName values were used as identifiers and output path components when generation ran without -c/--class-name. The fix adds sanitization via GenerationConfiguration.SanitizeClientClassName and SanitizeClientNamespaceName.
Likely exposure
Exposure is likely in developer workstations, CI jobs, or build systems that run kiota generate against OpenAPI descriptions from external, partner, generated, or otherwise weakly controlled sources.
Exploitation context
The bundle does not show KEV listing or confirmed active exploitation. Practical risk depends on whether an attacker can influence the OpenAPI description consumed by Kiota generation workflows.
Researcher notes
Public sources identify CWE-22 and CWE-94 impacts, with CVSS 4.0 score 9.3. The available bundle names affected versions and the fix, but does not provide evidence of active exploitation.
Mitigation direction
- Upgrade Microsoft Kiota to version 1.32.5 or later.
- Pin Kiota versions in CI and developer tooling.
- Avoid generating clients from untrusted or unreviewed OpenAPI descriptions.
- Use explicit class-name configuration where upgrade is delayed.
- Check Microsoft advisory and release notes for any additional guidance.
Validation and detection
- Inventory Kiota versions across CI, developer images, and repositories.
- Identify workflows running kiota generate without -c/--class-name.
- Review OpenAPI description sources for external or weakly trusted inputs.
- Check generated output trees for unexpected paths or source changes.
- Confirm upgraded runs use Kiota 1.32.5 or later.
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-22: File access and web shell behavior lookup
File traversal and upload weaknesses can lead teams to review file, web shell, execution, and collection telemetry. 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 lookupCWE-94: Code execution behavior lookup
Code execution and unsafe deserialization weaknesses often justify reviewing execution behavior and process telemetry. 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 lookupFile access behavior lookup
The CVE wording references file access or upload behavior, so file telemetry and web shell review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2026-59866 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
- Critical
- CVSS
- 9.3 (4.0)
- Known Exploited
- No
- Published
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
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:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N——GitHub_MVulnerability scoring details
Base CVSS 4.0 score
9.3CriticalVector: 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
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
- https://github.com/microsoft/kiota/security/advisories/GHSA-4vv7-jj25-4gh6CVE reference, GitHub_M · x_refsource_CONFIRM
- https://github.com/microsoft/kiota/pull/7884CVE reference, GitHub_M · x_refsource_MISC
- https://github.com/microsoft/kiota/commit/dc812dbbf88ef7edf53a890d36b2f9d1460e947dCVE reference, GitHub_M · x_refsource_MISC
- https://github.com/microsoft/kiota/releases/tag/v1.32.5CVE reference, GitHub_M · x_refsource_MISC
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.