Published:2015/10/01  Last Updated:2015/10/01

Python for Windows may insecurely load dynamic libraries


Python for Windows may use unsafe method for determining how to load DLL's.

Products Affected

  • Python for Windows


Python for Windows contains an issue with the DLL search path, which may lead to insecurely loading a DLL called readline.pyd.


Arbitray code may be executed with the privileges of python.exe.


Apply a workaround
Applying the following workaround will mitigate the effects of this issue

  • Ensure that a file with the name "readline.pyd" is not in the current directory prior to executing python.exe

Vendor Status

Vendor Status Last Update Vendor Notes
Python Vulnerable 2015/10/01


JPCERT/CC Addendum

Vulnerability Analysis by JPCERT/CC

Analyzed on 2015.10.01 (CVSS Base Metrics)

What is CVSS?

Measures Severity Description
Access Vector(AV) Local (L) Adjacent Network (A) Network (N) A vulnerability exploitable with network access means the vulnerable software is bound to the network stack and the attacker does not require local network access or local access. Such a vulnerability is often termed "remotely exploitable".
Access Complexity(AC) High (H) Medium (M) Low (L) The access conditions are somewhat specialized.
Authentication(Au) Multiple (M) Single (S) None (N) Authentication is not required to exploit the vulnerability.
Confidentiality Impact(C) None (N) Partial (P) Complete (C) There is considerable informational disclosure. Access to some system files is possible, but the attacker does not have control over what is obtained, or the scope of the loss is constrained.
Integrity Impact(I) None (N) Partial (P) Complete (C) Modification of some system files or information is possible, but the attacker does not have control over what can be modified, or the scope of what the attacker can affect is limited.
Availability Impact(A) None (N) Partial (P) Complete (C) There is reduced performance or interruptions in resource availability.

Base Score:6.8


Takashi Yoshikawa of Mitsui Bussan Secure Directions reported this vulnerability to IPA.
JPCERT/CC coordinated with the developer under Information Security Early Warning Partnership.

Other Information

JPCERT Reports
CERT Advisory
CPNI Advisory
CVE CVE-2015-5652
JVN iPedia JVNDB-2015-000141