Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2026-9669— bz2.BZ2Decompressor reuse after error can cause a stack buffer overflow

Quick assessment

Affected
Python Software Foundation CPython
Exploitation
Public or AI PoC available; prioritize validation
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

CPython是Python基金会的一个用C语言实现的Python解释器。 cpython存在安全漏洞，该漏洞源于解压错误后对象可被重用，若应用捕获OSError并使用相同解压器重试，特制输入可能导致解压器从无效内部状态恢复并对栈缓冲区进行越界写入，处理不可信数据时可能造成进程崩溃。

CVSS 8.2 · High EPSS 0.60% · P47

Possible ATT&CK Techniques 1 AI

T1203 · Exploitation for Client Execution

Affected Version Matrix 6

VendorProduct Version RangeStatus
Python Software Foundation CPython < 3.10.21 affected
3.11.0< 3.11.16 affected
3.12.0< 3.12.14 affected
3.13.0< 3.13.14 affected
3.14.0< 3.14.6 affected
3.15.0a1< 3.15.0b3 affected
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2026-9669

Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
bz2.BZ2Decompressor reuse after error can cause a stack buffer overflow
Source: CVE Program / CVE List V5
Vulnerability Description
bz2.BZ2Decompressor objects could be reused after a decompression error. If an application caught the resulting OSError and retried with the same decompressor, crafted input could cause the decompressor to resume from an invalid internal state and perform out-of-bounds writes to a stack buffer. This could crash the process when processing untrusted data.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Source: CVE Program / CVE List V5
Vulnerability Type
栈缓冲区溢出
Source: CVE Program / CVE List V5
Vulnerability Title
CPython 安全漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
CPython是Python基金会的一个用C语言实现的Python解释器。 cpython存在安全漏洞，该漏洞源于解压错误后对象可被重用，若应用捕获OSError并使用相同解压器重试，特制输入可能导致解压器从无效内部状态恢复并对栈缓冲区进行越界写入，处理不可信数据时可能造成进程崩溃。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)

Affected Products

Vendor Product Affected Versions CPE Subscribe
Python Software Foundation CPython 0 ~ 3.10.21 -

II. Public POCs for CVE-2026-9669

# POC Description Source Link Shenlong Link
AI-Generated POC Premium
Qwen3.6-35B-A3B · 6829 chars
Pro+ exclusive includes:
Vulnerability reproduction recording (real sandbox build + trigger, exclusive)
In-depth vulnerability mechanism
Trigger conditions & impact
Full executable POC code
Exploit chain & mitigation
POC zip download
100+ AI POC generations per month

III. Intelligence Information for CVE-2026-9669

请登录查看更多情报信息。

Patches & Fixes for CVE-2026-9669 (8)

Vendor Advisories for CVE-2026-9669 (2)

IV. Related Vulnerabilities

Same product: CPython
Same vendor: Python Software Foundation
Same weakness: CWE-121

V. Comments for CVE-2026-9669

No comments yet

Leave a comment