PatchSiren

PatchSiren cyber security CVE debrief

CVE-2026-5758 Mafintosh CVE debrief

CVE-2026-5758 is a medium-severity vulnerability affecting JavaScript, specifically in Mafintosh's protocol-buffers-schema version 3.6.0. The vulnerability is related to prototype pollution, which could allow an attacker to alter application logic, bypass security checks, cause a denial of service (DoS), or achieve remote code execution. Defenders should verify the presence of this vulnerability in their JavaScript dependencies and assess the potential impact on their systems. The CVE record and NVD entry provide information on the vulnerability, but details on exploitation, victims, or business impact are not available. The vulnerability's severity and potential impacts necessiate

Vendor
Mafintosh
Product
Protocol-buffers-schema parser
CVSS
MEDIUM 6.5
CISA KEV
Not listed in stored evidence
Original CVE published
2026-04-15
Original CVE updated
2026-10-26
Advisory published
2026-04-15
Advisory updated
2026-10-26

Who should care

Defenders responsible for JavaScript dependencies and systems using protocol-buffers-schema version 3.6.0 should assess their exposure and potential impact.

Why it matters

CVE-2026-5758 is a medium-severity vulnerability in JavaScript's protocol-buffers-schema version 3.6.0, allowing for prototype pollution. Defenders should verify the presence of this vulnerability in their dependencies, assess potential impacts, and consider updates or mitigations.

  • Alteration of application logic
  • Bypassing of security checks, requiring verification of current security measures
  • Potential for denial of service (DoS), impacting system availability
  • Possible achievement of remote code execution, necessitating immediate patching or mitigation

Technical summary

The vulnerability is caused by a prototype pollution issue in Mafintosh's protocol-buffers-schema version 3.6.0. This could allow an attacker to alter application logic, bypass security checks, cause a denial of service (DoS), or achieve remote code execution.

Defensive priority

Defenders should prioritize verifying the presence of this vulnerability in their JavaScript dependencies and assess the potential impact on their systems.

Recommended defensive actions

  • Verify the presence of protocol-buffers-schema version 3.6.0 in JavaScript dependencies
  • Assess the potential impact on systems using this dependency
  • Consider updating to a patched version if available

Evidence notes

The CVE record and NVD entry provide information on the vulnerability, but details on exploitation, victims, or business impact are not available. The vulnerability's severity and potential impacts necessitate verification of current security measures, assessment of potential impacts, and consideration of updates or mitigations. Defenders should verify the presence of protocol-buffers-schema version 3.6.0 in JavaScript dependencies, assess the potential impact on systems using this

Sources and references

Verified primary and authoritative sources

  • CVE-2026-5758 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-5758

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

  • CVE-2026-5758 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-5758

    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.