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asteval sandbox escape: arbitrary native memory read/write via numpy ctypes in default asteval Interpreter

Type: advisorySource: Official CVE List1 source record

asteval is a Python expression evaluator designed for restricted execution. Prior to 1.0.9, in asteval/astutils.py, the default Interpreter with numpy enabled exposes a ctypes type and permits from_address memory access. safe_getattr blocks the ctypes module but not reachable ctypes type objects, while attribute assignments use unfiltered setattr instead of safe_setattr. An attacker-controlled expression can derive an address with id, read memory through from_address, and write through an attribute assignment. The expression can read or corrupt arbitrary process memory, escape the intended sandbox, execute code, disclose secrets, or crash the host process. This issue is fixed in version 1.0.9.

Announced Group revision 1
Original source ↗

CVE-2026-102734

Primary source · Revision 1

Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.

Security context

Source reference: cve:CVE-2026-102734

asteval

Source reference: /containers/cna/affected/0/product

Affected versions
Not stated in this record
Fixed versions
Not stated in this record
Prerequisites
Not stated in this record

Structured affected-version data

Original package identities and version rules from this source.

[
  {
    "vendor": "lmfit",
    "product": "asteval",
    "versions": [
      {
        "status": "affected",
        "version": "< 1.0.9"
      }
    ]
  }
]
Related CVEs
CVE-2026-102734

Source reference: /cveMetadata/cveId

Publisher severity

medium

Source reference: /containers/cna/metrics

Event
#20787 · Revision 1
Added to Heist Feed
Publisher date
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