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CVE-2026-34935 MervinPraison CVE debrief

CVE-2026-34935 is a critical vulnerability in PraisonAI, a multi-agent teams system, that allows arbitrary OS command execution. The vulnerability exists in versions 4.5.15 to before 4.5.69, where the --mcp CLI argument is passed directly to shlex.split() and forwarded to anyio.open_process() without validation, allowlist check, or sanitization. This issue enables attackers to execute OS commands as the process user, potentially leading to system compromise. The vulnerability has been patched in version 4.5.69, and users are advised to apply this patch to prevent exploitation.

Vendor
MervinPraison
Product
PraisonAI
CVSS
CRITICAL 9.8
CISA KEV
Not listed in stored evidence
Original CVE published
2026-04-03
Original CVE updated
2026-07-24
Advisory published
2026-04-03
Advisory updated
2026-07-24

Who should care

Users of PraisonAI versions 4.5.15 to before 4.5.69 should apply the patch in version 4.5.69 to prevent arbitrary OS command execution. System administrators and security teams responsible for PraisonAI deployments need to assess their exposure, apply the patch, and monitor for suspicious activity. Additionally, users should review system logs for any signs of exploitation and implement compensating controls if immediate patching is not feasible.

Technical summary

The vulnerability in PraisonAI arises from the --mcp CLI argument being passed directly to shlex.split() and then to anyio.open_process() without any validation, allowlist check, or sanitization. This allows an attacker to execute arbitrary OS commands as the process user. The issue has been patched in version 4.5.69. Affected users should apply the patch and review system configurations to ensure no unauthorized access or exploitation has occurred.

Defensive priority

High

Recommended defensive actions

  • Apply the patch in version 4.5.69
  • Restrict access to the --mcp CLI argument
  • Implement input validation and sanitization for the --mcp CLI argument
  • Monitor for suspicious activity
  • Consider compensating controls such as Web Application Firewalls
  • Review system logs for signs of exploitation
  • Perform a thorough security audit of the affected systems

Evidence notes

The CVE record was published on 2026-04-03T23:17:05.693Z and last modified on 2026-07-24T22:10:00.140Z. The NVD entry is currently Analyzed. The vulnerability affects PraisonAI versions 4.5.15 to before 4.5.69. Users should verify their deployments and apply patches or mitigations accordingly. The CVE details are sourced from official records and may not reflect comprehensive information on all affected systems or potential workarounds.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-34935 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-34935

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

  • CVE-2026-34935 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-34935

    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.