CVE-2021-23336
published 2021-02-15CVE-2021-23336: The package python/cpython from 0 and before 3.6.13, from 3.7.0 and before 3.7.10, from 3.8.0 and before 3.8.8, from 3.9.0 and before 3.9.2 are vulnerable to…
PriorityP347medium5.9CVSS 3.1
AVNACHPRNUIRSUCNILAH
EPSS
35.96%
98.4th percentile
The package python/cpython from 0 and before 3.6.13, from 3.7.0 and before 3.7.10, from 3.8.0 and before 3.8.8, from 3.9.0 and before 3.9.2 are vulnerable to Web Cache Poisoning via urllib.parse.parse_qsl and urllib.parse.parse_qs by using a vector called parameter cloaking. When the attacker can separate query parameters using a semicolon (;), they can cause a difference in the interpretation of the request between the proxy (running with default configuration) and the server. This can result in malicious requests being cached as completely safe ones, as the proxy would usually not see the semicolon as a separator, and therefore would not include it in a cache key of an unkeyed parameter.
Affected
87 ranges· showing 25
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| ansible-automation-platform-25 | lightspeed-chatbot-rhel8 | — | — |
| ansible-automation-platform-26 | lightspeed-chatbot-rhel9 | — | — |
| ansible-automation-platform-27 | lightspeed-chatbot-rhel9 | — | — |
| ansible-automation-platform-27 | mcp-tools-rhel9 | — | — |
| apache | airflow | >= 1.0.0 < 1.10.15 | 1.10.15 |
| apache | airflow | >= 2.0.0 < 2.0.2 | 2.0.2 |
| container-native-virtualization | ocp-virt-validation-checkup-rhel9 | — | — |
| debian | debian_linux | — | — |
| debian | pypy3 | < pypy3 7.3.3+dfsg-3 (bookworm) | pypy3 7.3.3+dfsg-3 (bookworm) |
| debian | python-django | < pypy3 7.3.3+dfsg-3 (bookworm) | pypy3 7.3.3+dfsg-3 (bookworm) |
| debian | python2.7 | < pypy3 7.3.3+dfsg-3 (bookworm) | pypy3 7.3.3+dfsg-3 (bookworm) |
| debian | python3.9 | < pypy3 7.3.3+dfsg-3 (bookworm) | pypy3 7.3.3+dfsg-3 (bookworm) |
| djangoproject | django | >= 2.2 < 2.2.19 | 2.2.19 |
| djangoproject | django | >= 3.0 < 3.0.13 | 3.0.13 |
| djangoproject | django | >= 3.1 < 3.1.7 | 3.1.7 |
| exploit-intelligence-tech-preview | vulnerability-analysis-rhel9 | — | — |
| fastapiexpert | python-multipart | < 0.0.30 | 0.0.30 |
| fedoraproject | fedora | — | — |
| fedoraproject | fedora | — | — |
| fedoraproject | fedora | — | — |
| kludex | python-multipart | < 0.0.30 | 0.0.30 |
| kludex | python-multipart | >= 0 < 0.0.30 | 0.0.30 |
| msrc | cbl_mariner_1.0_arm | — | — |
| msrc | cbl_mariner_1.0_x64 | — | — |
| msrc | cbl_mariner_2.0_arm | — | — |
CVSS provenance
nvdv3.15.9MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:H
nvdv2.04.0MEDIUMAV:N/AC:H/Au:N/C:N/I:P/A:P
ghsa6.1MEDIUM
osv6.1MEDIUM
vendor_debian5.9MEDIUM
vendor_msrc5.9MEDIUM
vendor_redhat5.9MEDIUM
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Red Hat
python-multipart: Python-Multipart: Information disclosure due to parser differential in form data handling
vendor_redhat·2026-06-22·CVSS 5.9
CVE-2026-53538 [MEDIUM] CWE-1288 python-multipart: Python-Multipart: Information disclosure due to parser differential in form data handling
python-multipart: Python-Multipart: Information disclosure due to parser differential in form data handling
Python-Multipart is a streaming multipart parser for Python. Prior to 0.0.30, QuerystringParser treated ; as a field separator in application/x-www-form-urlencoded bodies, in addition to &. The WHATWG URL standard, modern browsers, and Python's urllib.parse (since the CVE-2021-23336 fix) treat only & as a separator. This creates a parser differential: the same bytes are tokenized into different fields than a WHATWG compliant intermediary would produce, allowing an attacker to smuggle extra form fields past an upstream body inspecting component. This vulnerability is fixed in 0.0.30.
A flaw was found in Python-Multipart, a tool used for processing web form data. A remote attacker co
Ubuntu
Django vulnerability
vendor_ubuntu·2021-02-22
CVE-2021-23336 Django vulnerability
Title: Django vulnerability
Summary: Django could allow unintended access to network services.
It was discovered that Django incorrectly accepted semicolons as query
parameters. A remote attacker could possibly use this issue to perform a
Web Cache Poisoning attack.
Instructions: In general, a standard system update will make all the necessary changes.
Red Hat
python: Web cache poisoning via urllib.parse.parse_qsl and urllib.parse.parse_qs by using a semicolon in query parameters
vendor_redhat·2021-02-13·CVSS 5.9
CVE-2021-23336 [MEDIUM] CWE-444 python: Web cache poisoning via urllib.parse.parse_qsl and urllib.parse.parse_qs by using a semicolon in query parameters
python: Web cache poisoning via urllib.parse.parse_qsl and urllib.parse.parse_qs by using a semicolon in query parameters
The package python/cpython from 0 and before 3.6.13, from 3.7.0 and before 3.7.10, from 3.8.0 and before 3.8.8, from 3.9.0 and before 3.9.2 are vulnerable to Web Cache Poisoning via urllib.parse.parse_qsl and urllib.parse.parse_qs by using a vector called parameter cloaking. When the attacker can separate query parameters using a semicolon (;), they can cause a difference in the interpretation of the request between the proxy (running with default configuration) and the server. This can result in malicious requests being cached as completely safe ones, as the proxy would usually not see the semicolon as a separator, and therefore would not include it in a cache key of
Microsoft
Web Cache Poisoning
vendor_msrc·2021-02-09·CVSS 5.9
CVE-2021-23336 [MEDIUM] CWE-444 Web Cache Poisoning
Web Cache Poisoning
FAQ: Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability?
One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up to date with the most recent and most secure versions of the open source libraries with which the distro is composed. Microsoft is committed to transparency in this work which is why we began publishing CSAF/VEX in October 2025. See this blog post for more information. If impact to additional products is identified, we will update the CVE to reflect this.
Mariner: Mariner
snyk: snyk
Customer Action Required: Yes
Remediation: CBL-Mariner Releases
Reference: https://learn.microsoft.com/en-us/azure/azure-linux
Debian
CVE-2021-23336: pypy3 - The package python/cpython from 0 and before 3.6.13, from 3.7.0 and before 3.7.1...
vendor_debian·2021·CVSS 5.9
CVE-2021-23336 [MEDIUM] CVE-2021-23336: pypy3 - The package python/cpython from 0 and before 3.6.13, from 3.7.0 and before 3.7.1...
The package python/cpython from 0 and before 3.6.13, from 3.7.0 and before 3.7.10, from 3.8.0 and before 3.8.8, from 3.9.0 and before 3.9.2 are vulnerable to Web Cache Poisoning via urllib.parse.parse_qsl and urllib.parse.parse_qs by using a vector called parameter cloaking. When the attacker can separate query parameters using a semicolon (;), they can cause a difference in the interpretation of the request between the proxy (running with default configuration) and the server. This can result in malicious requests being cached as completely safe ones, as the proxy would usually not see the semicolon as a separator, and therefore would not include it in a cache key of an unkeyed parameter.
Scope: local
bookworm: resolved (fixed in 7.3.3+dfsg-3)
bullseye: resolved (fixed in 7.3.3+dfsg-3)
fo
GHSA
python-multipart: Semicolon treated as querystring field separator enables parameter smuggling
ghsa·2026-06-15·CVSS 5.9
CVE-2026-53538 [MEDIUM] CWE-436 python-multipart: Semicolon treated as querystring field separator enables parameter smuggling
python-multipart: Semicolon treated as querystring field separator enables parameter smuggling
### Summary
`QuerystringParser` treated `;` as a field separator in `application/x-www-form-urlencoded` bodies, in addition to `&`. The [WHATWG URL standard](https://url.spec.whatwg.org/#urlencoded-parsing), modern browsers, and Python's `urllib.parse` (since the CVE-2021-23336 fix) treat only `&` as a separator. This creates a parser differential: the same bytes are tokenized into different fields than a WHATWG compliant intermediary would produce, allowing an attacker to smuggle extra form fields past an upstream body inspecting component.
### Details
In `python_multipart/multipart.py`, the `FIELD_NAME` and `FIELD_DATA` states located the next separator by scanning for `&` and, failing that
GHSA
Inconsistent Interpretation of HTTP Requests ('HTTP Request Smuggling')
ghsa_unreviewed·2022-02-08
CVE-2021-23336 [HIGH] CWE-444 Inconsistent Interpretation of HTTP Requests ('HTTP Request Smuggling')
Inconsistent Interpretation of HTTP Requests ('HTTP Request Smuggling')
The package python/cpython from 0 and before 3.6.13, from 3.7.0 and before 3.7.10, from 3.8.0 and before 3.8.8, from 3.9.0 and before 3.9.2 are vulnerable to Web Cache Poisoning via urllib.parse.parse_qsl and urllib.parse.parse_qs by using a vector called parameter cloaking. When the attacker can separate query parameters using a semicolon (;), they can cause a difference in the interpretation of the request between the proxy (running with default configuration) and the server. This can result in malicious requests being cached as completely safe ones, as the proxy would usually not see the semicolon as a separator, and therefore would not include it in a cache key of an unkeyed parameter.
GHSA
Cross-site Scripting in Apache Airflow
ghsa·2021-06-18·CVSS 6.1
CVE-2021-28359 [MEDIUM] CWE-79 Cross-site Scripting in Apache Airflow
Cross-site Scripting in Apache Airflow
The "origin" parameter passed to some of the endpoints like '/trigger' was vulnerable to XSS exploit. This issue affects Apache Airflow versions <1.10.15 in 1.x series and affects 2.0.0 and 2.0.1 and 2.x series. This is the same as CVE-2020-13944 & CVE-2020-17515 but the implemented fix did not fix the issue completely. Update to Airflow 1.10.15 or 2.0.2. Please also update your Python version to the latest available PATCH releases of the installed MINOR versions, example update to Python 3.6.13 if you are on Python 3.6. (Those contain the fix for CVE-2021-23336 https://nvd.nist.gov/vuln/detail/CVE-2021-23336).
OSV
Cross-site Scripting in Apache Airflow
osv·2021-06-18·CVSS 6.1
CVE-2021-28359 [MEDIUM] Cross-site Scripting in Apache Airflow
Cross-site Scripting in Apache Airflow
The "origin" parameter passed to some of the endpoints like '/trigger' was vulnerable to XSS exploit. This issue affects Apache Airflow versions <1.10.15 in 1.x series and affects 2.0.0 and 2.0.1 and 2.x series. This is the same as CVE-2020-13944 & CVE-2020-17515 but the implemented fix did not fix the issue completely. Update to Airflow 1.10.15 or 2.0.2. Please also update your Python version to the latest available PATCH releases of the installed MINOR versions, example update to Python 3.6.13 if you are on Python 3.6. (Those contain the fix for CVE-2021-23336 https://nvd.nist.gov/vuln/detail/CVE-2021-23336).
OSV
CVE-2021-28359: The "origin" parameter passed to some of the endpoints like '/trigger' was vulnerable to XSS exploit
osv·2021-05-02·CVSS 6.1
CVE-2021-28359 [MEDIUM] CVE-2021-28359: The "origin" parameter passed to some of the endpoints like '/trigger' was vulnerable to XSS exploit
The "origin" parameter passed to some of the endpoints like '/trigger' was vulnerable to XSS exploit. This issue affects Apache Airflow versions <1.10.15 in 1.x series and affects 2.0.0 and 2.0.1 and 2.x series. This is the same as CVE-2020-13944 & CVE-2020-17515 but the implemented fix did not fix the issue completely. Update to Airflow 1.10.15 or 2.0.2. Please also update your Python version to the latest available PATCH releases of the installed MINOR versions, example update to Python 3.6.13 if you are on Python 3.6. (Those contain the fix for CVE-2021-23336 https://nvd.nist.gov/vuln/detail/CVE-2021-23336).
OSV
CVE-2021-23336: The package python/cpython from 0 and before 3
osv·2021-02-15·CVSS 5.9
CVE-2021-23336 [MEDIUM] CVE-2021-23336: The package python/cpython from 0 and before 3
The package python/cpython from 0 and before 3.6.13, from 3.7.0 and before 3.7.10, from 3.8.0 and before 3.8.8, from 3.9.0 and before 3.9.2 are vulnerable to Web Cache Poisoning via urllib.parse.parse_qsl and urllib.parse.parse_qs by using a vector called parameter cloaking. When the attacker can separate query parameters using a semicolon (;), they can cause a difference in the interpretation of the request between the proxy (running with default configuration) and the server. This can result in malicious requests being cached as completely safe ones, as the proxy would usually not see the semicolon as a separator, and therefore would not include it in a cache key of an unkeyed parameter.
No detection rules found.
No public exploits indexed.
http://www.openwall.com/lists/oss-security/2021/02/19/4http://www.openwall.com/lists/oss-security/2021/05/01/2https://github.com/python/cpython/pull/24297https://lists.apache.org/thread.html/ra8ce70088ba291f358e077cafdb14d174b7a1ce9a9d86d1b332d6367%40%3Cusers.airflow.apache.org%3Ehttps://lists.apache.org/thread.html/rc005f4de9d9b0ba943ceb8ff5a21a5c6ff8a9df52632476698d99432%40%3Cannounce.apache.org%3Ehttps://lists.apache.org/thread.html/rf9fa47ab66495c78bb4120b0754dd9531ca2ff0430f6685ac9b07772%40%3Cdev.mina.apache.org%3Ehttps://lists.debian.org/debian-lts-announce/2021/02/msg00030.htmlhttps://lists.debian.org/debian-lts-announce/2021/04/msg00005.htmlhttps://lists.debian.org/debian-lts-announce/2021/04/msg00015.htmlhttps://lists.debian.org/debian-lts-announce/2023/09/msg00022.htmlhttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/3EPYWWFDV22CJ5AOH5VCE72DOASZZ255/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/3YKKDLXL3UEZ3J426C2XTBS63AHE46SM/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/46N6A52EGSXHJYCZWVMBJJIH4NWIV2B5/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FONHJIOZOFD7CD35KZL6SVBUTMBPGZGA/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HCQTCSP6SCVIYNIRUJC5X7YBVUHPLSC4/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HZTM7KLHFCE3LWSEVO2NAFLUHMGYMCRY/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/IHQDU7NXA7EWAE4W7VO6MURVJIULEPPR/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/KJXCMHLY7H3FIYLE4OKDYUILU2CCRUCZ/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LVNH6Z24IG3E67ZCQGGJ46FZB4XFLQNZ/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MNUN5SOMFL2BBKP6ZAICIIUPQKZDMGYO/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MP572OLHMS7MZO4KUPSCIMSZIA5IZZ62/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/N6VXJZSZ6N64AILJX4CTMACYGQGHHD5C/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NJSCSN722JO2E2AGPWD4NTGVELVRPB4R/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NODWHDIFBQE5RU5PUWUVE47JOT5VCMJ2/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OAGSWNGZJ6HQ5ISA67SNMK3CJRKICET7/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RSLQD5CCM75IZGAMBDGUZEATYU5YSGJ7/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SGIY6I4YS3WOXAK4SXKIEOC2G4VZKIR7/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TFTELUMWZE3KV3JB2H5EE6VFRZFRD5MV/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/W2LSKBEFI5SYEY5FM6ICZVZM5WRQUCS4/https://security.gentoo.org/glsa/202104-04https://security.netapp.com/advisory/ntap-20210326-0004/https://snyk.io/blog/cache-poisoning-in-popular-open-source-packages/https://snyk.io/vuln/SNYK-UPSTREAM-PYTHONCPYTHON-1074933https://www.oracle.com//security-alerts/cpujul2021.htmlhttps://www.oracle.com/security-alerts/cpuApr2021.htmlhttps://www.oracle.com/security-alerts/cpujan2022.htmlhttps://www.oracle.com/security-alerts/cpuoct2021.htmlhttp://www.openwall.com/lists/oss-security/2021/02/19/4http://www.openwall.com/lists/oss-security/2021/05/01/2https://github.com/python/cpython/pull/24297https://lists.apache.org/thread.html/ra8ce70088ba291f358e077cafdb14d174b7a1ce9a9d86d1b332d6367%40%3Cusers.airflow.apache.org%3Ehttps://lists.apache.org/thread.html/rc005f4de9d9b0ba943ceb8ff5a21a5c6ff8a9df52632476698d99432%40%3Cannounce.apache.org%3Ehttps://lists.apache.org/thread.html/rf9fa47ab66495c78bb4120b0754dd9531ca2ff0430f6685ac9b07772%40%3Cdev.mina.apache.org%3Ehttps://lists.debian.org/debian-lts-announce/2021/02/msg00030.htmlhttps://lists.debian.org/debian-lts-announce/2021/04/msg00005.htmlhttps://lists.debian.org/debian-lts-announce/2021/04/msg00015.htmlhttps://lists.debian.org/debian-lts-announce/2023/09/msg00022.htmlhttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/3EPYWWFDV22CJ5AOH5VCE72DOASZZ255/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/3YKKDLXL3UEZ3J426C2XTBS63AHE46SM/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/46N6A52EGSXHJYCZWVMBJJIH4NWIV2B5/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FONHJIOZOFD7CD35KZL6SVBUT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2021-02-15
Published