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PatchSiren cyber security CVE debrief

CVE-2026-76905 getkin CVE debrief

A vulnerability in the kin-openapi Go project for handling OpenAPI files allows for a denial-of-service (DoS) attack. The issue arises from the openapi3filter.convertParseError function in openapi3filter/validation_error_encoder.go, which dereferences e.Parameter.In without checking if e.Parameter is nil. This can lead to a panic in applications that render validation errors through openapi3filter.ConvertErrors or ValidationErrorEncoder when a malformed non-string scalar field is present in a multipart/form-data request body. The vulnerability is fixed in version 0.141.0.

Vendor
getkin
Product
kin-openapi
CVSS
HIGH 7.5
CISA KEV
Not listed in stored evidence
Original CVE published
2026-08-21
Original CVE updated
2026-09-09
Advisory published
2026-08-21
Advisory updated
2026-09-09

Who should care

Developers and administrators using kin-openapi versions between 0.10.0 and 0.141.0 should be aware of this vulnerability and take steps to mitigate it. This includes updating to version 0.141.0 or later, implementing input validation and sanitization for request bodies, and monitoring for and handling validation errors securely. Additionally, operators and security teams should review the official advisory and CVE record to validate affected scope, severity, and vendor guidance, and plan vendor-supported updates or mitigations through normal change control where exposure is confirmed. Vulnerability management teams should track exceptions, retest remediated assets, and close the item only after evidence is documented. Security teams should also review compensating controls for exposed systems while remediation is scheduled and verified, and check relevant monitoring, detection, and logs for exposed assets that need extra review. Asset inventory management should confirm whether affected product deployments exist in managed environments and assign an owner for follow-up. Change management processes should be used to implement and verify remediation, and source tracking should be used to monitor for potential attacks. Rollback/change windows should be used to minimize downtime during remediation. Monitoring and detection capabilities should be reviewed to ensure they can detect potential attacks. Asset inventory and configuration management should be used to identify and track affected systems. Security teams should also consider implementing additional security controls, such as web application firewalls or intrusion detection systems, to detect and prevent potential attacks. Finally, security teams should review and update their incident response plans to ensure they are prepared to respond to potential attacks exploiting this vulnerability. IT operations teams should also review and update their procedures for handling validation errors and denial-of-service attacks. Compliance teams should review and update their compliance procedures to ensure they are aligned with the updated security controls. Audit teams should review and update their audit procedures to

Technical summary

The openapi3filter.convertParseError function in openapi3filter/validation_error_encoder.go does not check if e.Parameter is nil before dereferencing e.Parameter.In. This can cause applications that use openapi3filter.ConvertErrors or ValidationErrorEncoder to panic when encountering a malformed non-string scalar field in a multipart/form-data request body. The vulnerability is fixed in version 0.141.0. Affected applications should be updated to this version or later to prevent potential denial-of-service attacks. Developers should also implement input validation and sanitization for request bodies to mitigate this vulnerability.

Defensive priority

High priority due to potential for DoS attacks

Recommended defensive actions

  • Update kin-openapi to version 0.141.0 or later
  • Implement input validation and sanitization for request bodies
  • Monitor for and handle validation errors securely
  • Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up.
  • Review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance.
  • Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed.
  • Track exceptions, retest remediated assets, and close the item only after evidence is documented.

Evidence notes

The evidence from the CVE record and NVD detail suggests that the vulnerability exists in kin-openapi versions from 0.10.0 to 0.141.0. The fix is included in version 0.141.0. To verify, defenders should check the version of kin-openapi in use and review the official advisory for specific guidance on affected scope and severity. Additionally, defenders should monitor for and handle validation errors securely to prevent potential denial-of-service attacks.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-76905 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-76905

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2026-76905 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-76905

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.