PraisonAI: execute_code sandbox bypass: str.format C-level attribute access reads every blocklisted dunder

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

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

EPSS

• CVE-2026-57120: 0.56% estimated exploitation activity in the next 30 days; percentile 46.33 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary The executecode tool's subprocess sandbox advertises a three-layer defense (AST validation, text-pattern blocklist, restricted builtins). In sandbox mode (the default) only two layers are active — the text-pattern blocklist is skipped — and both remaining layers are bypassed by combining two CPython semantics: 1. Runtime string assembly. The AST validator (src/praisonai-agents/praisonaiagents/tools/pythontools.py:75) enumerates blocked dunder names against ast.Attribute.attr, ast.Call.func.id, and ast.Constant string-substring. Names assembled at runtime (e.g. ""2 + "class" + ""2) appear in the AST as multiple short ast.Constant nodes, none containing a blocked substring, so the static check passes. 2. C-level attribute access via format-spec. str.format / str.formatmap resolve dotted field references through CPython's internal PyObjectGetAttr (dostringformat → getfield). This C path never consults the Python-level getattr binding. The sandbox's safegetattr wrapper…

Published by the source

18 Jun 2026, 13:55 UTC

Last modified by the source

23 Jul 2026, 15:11 UTC

Source last checked

26 Oct 2026, 13:49 UTC

1. Revision 2 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-pv2j-rghr-v5r9

2. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-pv2j-rghr-v5r9

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# Patch Next advisory brief: CVE-2026-57120

Advisory: PraisonAI: execute_code sandbox bypass: str.format C-level attribute access reads every blocklisted dunder
IDs: CVE-2026-57120, GHSA-pv2j-rghr-v5r9
Record: https://patchnext.com/advisories/cve-2026-57120 (revision 2, source checked 26 Oct 2026, 13:49 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 6.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: praisonaiagents 1.6.59. A vendor fix does not mean a deployment is fixed.

## Affected components
- PyPI praisonaiagents: affected < 1.6.59; fixed in 1.6.59

## Suggested inspection (read-only)
- `python -m pip show praisonaiagents`: prints the installed version. Run with the environment that serves production active.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on praisonaiagents.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GHSA-pv2j-rghr-v5r9 (OSV record GHSA-pv2j-rghr-v5r9 lists affected ranges: PyPI praisonaiagents >=0 <1.6.59 (fixed))
- Verified: https://github.com/advisories/GHSA-pv2j-rghr-v5r9 (GitHub-reviewed advisory GHSA-pv2j-rghr-v5r9 lists affected ranges: PyPI praisonaiagents >=0 <1.6.59)

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