CVE-2026-3644
Incomplete control character validation in http.cookies
Description
The fix for CVE-2026-0672, which rejected control characters in http.cookies.Morsel, was incomplete. The Morsel.update(), |= operator, and unpickling paths were not patched, allowing control characters to bypass input validation. Additionally, BaseCookie.js_output() lacked the output validation applied to BaseCookie.output().
INFO
Published Date :
March 16, 2026, 6:16 p.m.
Last Modified :
March 16, 2026, 6:16 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-3644
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 4.0 | MEDIUM | 28c92f92-d60d-412d-b760-e73465c3df22 | ||||
| CVSS 4.0 | MEDIUM | [email protected] |
Solution
- Update HTTP cookie handling code.
- Patch Morsel.update(), |= operator, and unpickling.
- Validate output in BaseCookie.js_output().
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-3644.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-3644 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-3644
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-3644 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-3644 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by [email protected]
Mar. 16, 2026
Action Type Old Value New Value Added Description The fix for CVE-2026-0672, which rejected control characters in http.cookies.Morsel, was incomplete. The Morsel.update(), |= operator, and unpickling paths were not patched, allowing control characters to bypass input validation. Additionally, BaseCookie.js_output() lacked the output validation applied to BaseCookie.output(). Added CVSS V4.0 AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added Reference https://github.com/python/cpython/commit/57e88c1cf95e1481b94ae57abe1010469d47a6b4 Added Reference https://github.com/python/cpython/commit/62ceb396fcbe69da1ded3702de586f4072b590dd Added Reference https://github.com/python/cpython/commit/d16ecc6c3626f0e2cc8f08c309c83934e8a979dd Added Reference https://github.com/python/cpython/issues/145599 Added Reference https://github.com/python/cpython/pull/145600 Added Reference https://mail.python.org/archives/list/[email protected]/thread/H6CADMBCDRFGWCMOXWUIHFJNV43GABJ7/