CVE-2025-56005
Summary
| CVE | CVE-2025-56005 |
|---|---|
| State | PUBLISHED |
| Assigner | mitre |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-01-20 19:15:49 UTC |
| Updated | 2026-07-20 12:17:00 UTC |
| Description | An undocumented and unsafe feature in the PLY (Python Lex-Yacc) library 3.11 allows Remote Code Execution (RCE) via the `picklefile` parameter in the `yacc()` function. This parameter accepts a `.pkl` file that is deserialized with `pickle.load()` without validation. Because `pickle` allows execution of embedded code via `__reduce__()`, an attacker can achieve code execution by passing a malicious pickle file. The parameter is not mentioned in official documentation or the GitHub repository, yet it is active in the PyPI version. This introduces a stealthy backdoor and persistence risk. NOTE: A third-party states that this vulnerability should be rejected because the proof of concept does not demonstrate arbitrary code execution and fails to complete successfully. |
Risk And Classification
Primary CVSS: v3.1 9.8 CRITICAL from ADP
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS: 0.169030000 probability, percentile 0.967160000 (date 2026-07-20)
Problem Types: CWE-502 | n/a | CWE-502 CWE-502 Deserialization of Untrusted Data | CWE-502 Deserialization of Untrusted Data
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | ADP | DECLARED | 9.8 | CRITICAL | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| 3.1 | ADP | CVSS | 7.8 | HIGH | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| 3.1 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | Secondary | 9.8 | CRITICAL | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| 3.1 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | Secondary | 7.8 | HIGH | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
LowPrivileges Required
NoneUser Interaction
NoneScope
UnchangedConfidentiality
HighIntegrity
HighAvailability
HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD Known Affected Configurations (CPE 2.3)
Vendor Declared Affected Products
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| www.openwall.com/lists/oss-security/2026/01/23/4 | af854a3a-2127-422b-91ae-364da2661108 | www.openwall.com | Exploit, Mailing List |
| www.openwall.com/lists/oss-security/2026/01/23/5 | af854a3a-2127-422b-91ae-364da2661108 | www.openwall.com | Mailing List |
| github.com/tom025/ply_exploit_rejection | [email protected] | github.com | Exploit, Mitigation, Third Party Advisory |
| www.openwall.com/lists/oss-security/2026/01/30/1 | af854a3a-2127-422b-91ae-364da2661108 | www.openwall.com | |
| bugzilla.redhat.com/show_bug.cgi | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | bugzilla.redhat.com | |
| www.openwall.com/lists/oss-security/2026/01/29/2 | af854a3a-2127-422b-91ae-364da2661108 | www.openwall.com | Mailing List |
| security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-56005.json | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | security.access.redhat.com | |
| github.com/bohmiiidd/Undocumument_RCE_PLY-yacc-CVE-2025-56005 | [email protected] | github.com | Exploit, Third Party Advisory |
| www.openwall.com/lists/oss-security/2026/01/29/1 | af854a3a-2127-422b-91ae-364da2661108 | www.openwall.com | Exploit, Mailing List |
| access.redhat.com/security/cve/CVE-2025-56005 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| github.com/tom025/ply_exploit_rejection/issues/1 | [email protected] | github.com | |
| github.com/bohmiiidd/Undocumented-RCE-in-PLY | [email protected] | github.com | Exploit, Third Party Advisory |
| www.openwall.com/lists/oss-security/2026/01/28/5 | af854a3a-2127-422b-91ae-364da2661108 | www.openwall.com | Exploit, Mailing List |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
Additional Advisory Data
| Source | Time | Event |
|---|---|---|
| ADP | 2026-01-20T19:00:55.111Z | Reported to Red Hat. |
| ADP | 2026-01-20T00:00:00.000Z | Made public. |
There are currently no legacy QID mappings associated with this CVE.