カテゴリー: Programming

Pythonの脆弱性

Googleがクラウドコンピューティングの言語としてPythonを採用したのでセキュリティ研究家が脆弱性を調査し、今年はPythonの脆弱性が多く報告されるはず、とこのブログで予想しています。また新たな脆弱性が報告されているので書いておきます。

今回は整数オーバーフローが多いので、整数オーバーフローを中心に調査したのだと思われます。
Python 2.5.3以上でないと穴だらけと言えますが….

http://python.org/download/

と言った状況のようです。

しかし、予想通りとはいえ数が多いですね。

CVE-2008-3144
Multiple integer overflows in the PyOS_vsnprintf function in Python/mysnprintf.c in Python 2.5.2 and earlier allow context-dependent attackers to cause a denial of service (memory corruption) or have unspecified other impact via crafted input to string formatting operations. NOTE: the handling of certain integer values is also affected by related integer underflows and an off-by-one error.

CVE-2008-3143
Multiple integer overflows in Python before 2.5.2 might allow context-dependent attackers to have an unknown impact via vectors related to (1) Include/pymem.h; (2) _csv.c, (3) _struct.c, (4) arraymodule.c, (5) audioop.c, (6) binascii.c, (7) cPickle.c, (8) cStringIO.c, (9) cjkcodecs/multibytecodec.c, (10) datetimemodule.c, (11) md5.c, (12) rgbimgmodule.c, and (13) stropmodule.c in Modules/; (14) bufferobject.c, (15) listobject.c, and (16) obmalloc.c in Objects/; (17) Parser/node.c; and (18) as…

CVE-2008-3142
Multiple buffer overflows in Python 2.5.2 and earlier on 32bit platforms allow context-dependent attackers to cause a denial of service (crash) or have unspecified other impact via a long string that leads to incorrect memory allocation during Unicode string processing, related to the unicode_resize function and the PyMem_RESIZE macro.

CVE-2008-2316
Integer overflow in _hashopenssl.c in the hashlib module in Python 2.5.2 and earlier might allow context-dependent attackers to defeat cryptographic digests, related to “partial hashlib hashing of data exceeding 4GB.”

CVE-2008-2315
Multiple integer overflows in Python 2.5.2 and earlier allow context-dependent attackers to have an unknown impact via vectors related to the (1) stringobject, (2) unicodeobject, (3) bufferobject, (4) longobject, (5) tupleobject, (6) stropmodule, (7) gcmodule, and (8) mmapmodule modules.

Python 2.5.3にリモートコード実行の可能性がある脆弱性

最近CVEのコピー&ペーストが続いていますがこのブログに書いていた予想通りの展開なのでまたコピーです。

コアとはいえあまり重要ではない箇所の脆弱性ですが、Python 2.5.3にリモートコード実行の可能性がある脆弱性がレポートされています。

CVE-2008-1679

Overview

Multiple integer overflows in imageop.c in Python before 2.5.3 allow context-dependent attackers to cause a denial of service (crash) and possibly execute arbitrary code via crafted images that trigger heap-based buffer overflows. NOTE: this issue is due to an incomplete fix for CVE-2007-4965.

Impact

CVSS Severity (version 2.0):
CVSS v2 Base score: 6.8 (Medium) (AV:N/AC:M/Au:N/C:P/I:P/A:P) (legend)
Impact Subscore: 6.4
Exploitability Subscore: 8.6

Access Vector: Network exploitable , Victim must voluntarily interact with attack mechanism
Access Complexity: Medium
Authentication: Not required to exploit
Impact Type: Provides unauthorized access, Allows partial confidentiality, integrity, and availability violation , Allows unauthorized disclosure of information , Allows disruption of service

直したつもりが直っていないのはよくある事です。直したはずだったCVE-2007-4965は以下の通りです。

CVE-2007-4965

Overview

Multiple integer overflows in the imageop module in Python 2.5.1 and earlier allow context-dependent attackers to cause a denial of service (application crash) and possibly obtain sensitive information (memory contents) via crafted arguments to (1) the tovideo method, and unspecified other vectors related to (2) imageop.c, (3) rbgimgmodule.c, and other files, which trigger heap-based buffer overflows.

関連：
Python 2.5.2以下に任意コード実行の脆弱性
GoogleのPython採用と脆弱性情報の関係