CVE-2026-55244

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Source
https://cve.org/CVERecord?id=CVE-2026-55244
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-55244.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-55244
Aliases
Downstream
CGA (6)
DEBIAN (1)
ECHO (1)
openSUSE (1)
UBUNTU (1)
Related
Published
2026-09-14T20:00:24Z
Modified
2026-10-28T02:30:42Z
Severity
  • 5.0 (Medium) CVSS_V3 - CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H CVSS Calculator
Summary
ASTEVAL: Sandbox Escape via BaseException Subclasses
Details

ASTEVAL is an evaluator of Python expressions and statements. Prior to 1.0.9, FROM_PY in asteval/astutils.py exposes BaseException, SystemExit, KeyboardInterrupt, and GeneratorExit to expressions evaluated by asteval.Interpreter.eval(), while run() and eval() in asteval/asteval.py catch Exception rather than these non-Exception BaseException subclasses. When an attacker-controlled expression raises one of these classes, on_raise() passes the class to raise_exception(), and the resulting exception bypasses the interpreter's safety handlers and propagates into the calling application. A consuming service that evaluates untrusted expressions can therefore be terminated or have signal and cleanup handling disrupted, causing denial of service. The separately documented read-only open() capability is not part of this vulnerability. This issue is fixed in version 1.0.9.

Database specific 
{
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
        "CWE-248"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/55xxx/CVE-2026-55244.json"
}
References

Affected packages

Git / github.com/lmfit/asteval

Affected ranges

Type
GIT
Repo
https://github.com/lmfit/asteval
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
0b359d0b03195d1288af656e98730ab691b04f5a
Fixed
9c625b3674f8d05f206708bb85afca17a87694a4
Fixed
c49c99a67acb63eb7410231932250bd820380e45
Database specific
Show details 
{
    "extracted_events": [
        {
            "range": [
                {
                    "introduced": "0"
                },
                {
                    "fixed": "1.0.9"
                }
            ],
            "source": "AFFECTED_FIELD",
            "strategy": "StringRangeExpression"
        },
        {
            "range": [
                {
                    "fixed": "9c625b3674f8d05f206708bb85afca17a87694a4"
                }
            ],
            "source": "REFERENCES_COMMIT"
        },
        {
            "range": [
                {
                    "fixed": "c49c99a67acb63eb7410231932250bd820380e45"
                }
            ],
            "source": "REFERENCES_COMMIT"
        },
        {
            "original_tag": "1.0.9",
            "range": [
                {
                    "fixed": "0b359d0b03195d1288af656e98730ab691b04f5a"
                }
            ],
            "source": "REFERENCES_TAG"
        }
    ]
}

Affected versions

0.*
0.9
0.9.1
0.9.10
0.9.11
0.9.12
0.9.13
0.9.14
0.9.15
0.9.16
0.9.17
0.9.18
0.9.19
0.9.2
0.9.20
0.9.21
0.9.22
0.9.23
0.9.24
0.9.25
0.9.26
0.9.27
0.9.28
0.9.29
0.9.3
0.9.3.1
0.9.30
0.9.31
0.9.32
0.9.33
0.9.4
0.9.5
0.9.6
0.9.7
0.9.9
1.*
1.0.0
1.0.1
1.0.2
1.0.3
1.0.4
1.0.5
1.0.6
1.0.7
1.0.8

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-55244.json"