Previously, `getInnerText()` recursively used `list.extend()` on strings,
which added each character from child nodes as a separate list element.
On deeply nested XML content, this caused the overall deserialization
work to grow quadratically with input size, potentially allowing
disproportionate CPU consumption for crafted XML.
The fix separates collection of inner texts from joining them, so that
each subtree is joined only once, reducing the complexity to linear in
the size of the input. These changes also include a mitigation for a
xml.dom.minidom performance issue.
Thanks Seokchan Yoon (https://ch4n3.kr/) for report.
Co-authored-by: Jacob Walls <jacobtylerwalls@gmail.com>
Co-authored-by: Natalia <124304+nessita@users.noreply.github.com>
Backport of 50efb718b3 from main.
Follow-up to CVE-2025-57833.
Thanks Stackered for the report, and Simon Charette and Mariusz Felisiak
for the reviews.
Backport of 5b90ca1e75 from main.
Ideally, this will be reverted when an upstream solution is available for
https://github.com/python/cpython/issues/141560.
Thanks Patrick Rauscher for the report and Augusto Pontes for the
first iteration and test.
Backport of 34186e731c from main.
The fix landed in a8cf8c292c will be
backported to 5.1 and 4.2 since the 2048 limit was rolled out as part of
the security release for CVE-2025-64458.
Backport of 18b13cf6c4 from main.
Refs CVE-2025-64458.
The previous limit of 2048 characters reused the URLValidator constant
and proved too restrictive for legitimate redirects to some third-party
services. This change introduces a separate `MAX_URL_REDIRECT_LENGTH`
constant (defaulting to 16384) and uses it in HttpResponseRedirectBase.
Thanks Jacob Walls for report and review.
Backport of a8cf8c292c from main.
Added warning in DateField documentation about type differences when using
timedelta on PostgreSQL and MySQL. Mentioned Cast() and integer arithmetic
solutions.
Backport of 55af4749b9 from main.
Regression in b8e5a8a9a2.
Refs #36404.
The replace_expressions method was innapropriately dealing with falsey
but not None source expressions causing them to also be potentially
evaluated when __bool__ was invoked (e.g. QuerySet.__bool__ evaluates
the queryset).
The changes introduced in b8e5a8a9a2, which were to deal with a similar
issue, surfaced the problem as aggregation over an annotated queryset
requires an inlining (or pushdown) of aggregate references which is
achieved through replace_expressions.
In cases where an empty Q object was provided as an aggregate filter,
such as when the admin facetting feature was used as reported, it would
wrongly be turned into None, instead of an empty WhereNode, causing a
crash at aggregate filter compilation.
Note that the crash signature differed depending on whether or not the
backend natively supports aggregate filtering
(supports_aggregate_filter_clause) as the fallback, which makes use
Case / When expressions, would result in a TypeError instead of a
NoneType AttributeError.
Thanks Rafael Urben for the report, Antoliny and Youngkwang Yang for
the triage.
Backport of 2a6e0bd72d from main
Updated the EmailValidator docs in docs/ref/validators.txt to explicitly
state that it validates an email address, to avoid confusion with
validating email message content.
Backport of a4f7674134 from main.
Thanks Seokchan Yoon for the report, Markus Holtermann for the
triage, and Jake Howard for the review.
Follow-up to CVE-2025-27556 and 39e2297210.
Backport of c880530ddd from main.
Proxy models subclassing a model with a CompositePrimaryKey were
incorrectly reporting check errors because the check that requires only
local fields to be used in a composite pk was evaluated against the proxy
subclass, which has no fields.
To fix this, composite pk field checks are not evaluated against
proxy subclasses, as none of the checks are applicable to proxy
subclasses. This also has the benefit of not double-reporting real check
errors from an invalid superclass pk.
Thanks Clifford Gama for the review.
Backport of 74564946c3 from main.
