CVE-2021-3177
- State
- Published
- Severity
- 9.8 Critical
- Published
- Jan 19, 2021
- Updated
- Oct 14, 2026
- Reserved
- Jan 19, 2021
Description
Python 3.x through 3.9.1 has a buffer overflow in PyCArg_repr in _ctypes/callproc.c, which may lead to remote code execution in certain Python applications that accept floating-point numbers as untrusted input, as demonstrated by a 1e300 argument to c_double.from_param. This occurs because sprintf is used unsafely.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 9.8 Critical | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H | CISA-ADP |
Weaknesses
- CWE-120 Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
Affected Products
| Product | Versions |
|---|---|
n/an/a |
|
References
- https://bugs.python.org/issue42938
- https://github.com/python/cpython/pull/24239
- https://python-security.readthedocs.io/vuln/ctypes-buffer-overflow-pycarg_repr.html
- FEDORA-2021-faf88b9499vendor-advisory
- FEDORA-2021-cc3ff94cfcvendor-advisory
- GLSA-202101-18vendor-advisory
- FEDORA-2021-e3a5a74610vendor-advisory
- FEDORA-2021-ced31f3f0cvendor-advisory
- FEDORA-2021-42ba9feb47vendor-advisory
- FEDORA-2021-076a2dccbavendor-advisory
- FEDORA-2021-851c6e4e2dvendor-advisory
- FEDORA-2021-66547ff92dvendor-advisory
- FEDORA-2021-17668e344avendor-advisory
- FEDORA-2021-d5cde50865vendor-advisory
- FEDORA-2021-7547ad987fvendor-advisory
- FEDORA-2021-f4fd9372c7vendor-advisory
- FEDORA-2021-3352c1c802vendor-advisory
- [mina-dev] 20210225 [jira] [Created] (FTPSERVER-500) Security vulnerability in common/lib/log4j-1.2.17.jarmailing-list
- FEDORA-2021-907f3bacaevendor-advisory
- [debian-lts-announce] 20210405 [SECURITY] [DLA 2619-1] python3.5 security updatemailing-list
- https://www.oracle.com//security-alerts/cpujul2021.html
- https://news.ycombinator.com/item?id=26185005
- https://security.netapp.com/advisory/ntap-20210226-0003/
- https://www.oracle.com/security-alerts/cpuoct2021.html
- https://www.oracle.com/security-alerts/cpujan2022.html
- [debian-lts-announce] 20220212 [SECURITY] [DLA 2919-1] python2.7 security updatemailing-list
- https://www.oracle.com/security-alerts/cpujul2022.html
- [debian-lts-announce] 20230524 [SECURITY] [DLA 3432-1] python2.7 security updatemailing-list
- https://cert-portal.siemens.com/productcert/html/ssa-398330.html
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