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NVD / CVE Program· CNA GitHub_M

CVE-2026-39888: PraisonAIAgents has a sandbox escape via exception frame traversal in `execute_code` (subprocess mode)

CriticalCVSS 9.9 · v3.1—No exploit Fix available

Noroxi assessment

Priority: Monitor (action score 39/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.50% (FIRST EPSS).
  • Anyone who can reach it over the internet can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: MervinPraison praisonaiagents 1.5.115.

Low priority for now. Upgrade to MervinPraison praisonaiagents 1.5.115 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

PraisonAI is a multi-agent teams system. Prior to 1.5.115, execute_code() in praisonaiagents.tools.python_tools defaults to sandbox_mode="sandbox", which runs user code in a subprocess wrapped with a restricted __builtins__ dict and an AST-based blocklist. The AST blocklist embedded inside the subprocess wrapper (blocked_attrs of python_tools.py) contains only 11 attribute names — a strict subset of the 30+ names blocked in the direct-execution path. The four attributes that form a frame-traversal chain out of the sandbox are all absent from the subprocess list (__traceback__, tb_frame, f_back, and f_builtins). Chaining these attributes through a caught exception exposes the real Python builtins dict of the subprocess wrapper frame, from which exec can be retrieved and called under a non-blocked variable name — bypassing every remaining security layer. This vulnerability is fixed in 1.5.115.

Published
Apr 8, 2026
Updated
Jul 24, 2026
EPSS
0.5% · 43th percentile

Report tools

JSON

Action score

39

Monitor

Low priority for now.

CVSS
39 / 40 · 9.9 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.5%

CISA SSVC decision

Exploitation
proof of concept
Automatable
no
Technical impact
total

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
9.9
CNA · GitHub_M
10.0
0.1 point gap

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2026-39888

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
praisonpraisonai

Versions reported by the vendor

Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.

  • MervinPraison praisonaiagents

    • < 1.5.115affected

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • praison praisonaibefore 1.5.115

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
PyPIpraisonaiagentsbefore 1.5.1151.5.115

Same product

praison: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-40114PraisonAI has Server-Side Request Forgery via Unvalidated webhook_url in Jobs API
    40Plan
  • CVE-2026-39305Arbitrary File Write / Path Traversal in Action Orchestrator
    40Plan
  • CVE-2026-34955PraisonAI: Sandbox Escape via shell=True and Bypassable Blocklist in SubprocessSandbox
    40Plan

Published before and after this one in the same product

  • ← EarlierCVE-2026-39307Apr 7, 2026 · PraisonAI has an Arbitrary File Write (Zip Slip) in Templates Extraction
    32Monitor
  • ← EarlierCVE-2026-39308Apr 7, 2026 · PraisonAI recipe registry publish path traversal allows out-of-root file write
    28Monitor
  • Later →CVE-2026-39889Apr 8, 2026 · PraisonAI has Unauthenticated SSE Event Stream Exposes All Agent Activity in A2U Server
    30Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
MervinPraison praisonaiagents1.5.115 · descriptionVendor (CNA)
PyPI:praisonaiagents1.5.115Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

Not on record for this CVE: EPSS history · patch commit or PR link · researcher credit · variant or chain candidate · public bounty program.

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • A low-privileged account is enough.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
high · data can be read
Integrity
high · data or configuration can be modified
Availability
high · the service can be disrupted

Impact can extend beyond the vulnerable component (scope changes).

Attack vector
Network
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Changed
Confidentiality impact
High
Integrity impact
High
Availability impact
High

Weakness class (CWE)

CWE-657 · Violation of Secure Design Principles

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

nvd-primary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

References

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records