diff --git a/docs/releasenotes/12.2.0.rst b/docs/releasenotes/12.2.0.rst
index c03a2848237..f40819035fa 100644
--- a/docs/releasenotes/12.2.0.rst
+++ b/docs/releasenotes/12.2.0.rst
@@ -25,7 +25,7 @@ these checks did not consider integer overflow. This has been corrected.
 
 When parsing a PDF, if a trailer refers to itself, or a more complex cyclic loop
 exists, then an infinite loop occurs. Pillow now keeps a record of which trailers it
-has already processed. PdfParser was added in Pillow 4.2.0.
+has already processed. PdfParser was added in Pillow 5.1.0.
 
 :cve:`2026-42308`: Integer overflow when processing fonts
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
diff --git a/docs/releasenotes/12.3.0.rst b/docs/releasenotes/12.3.0.rst
index 534f22b86d3..0699dfba66a 100644
--- a/docs/releasenotes/12.3.0.rst
+++ b/docs/releasenotes/12.3.0.rst
@@ -4,39 +4,84 @@
 Security
 ========
 
-TODO
-^^^^
+Prevent decompression bomb when parsing PDF
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-TODO
+When parsing a PDF, ``PdfStream.decode()`` attempts to decompress data without any
+limit. A default maximum of ``ImageFile.SAFEBLOCK`` has been added. ``PdfParser`` was
+added in Pillow 5.1.0. Reported by `redyank <https://github.com/redyank>`__.
 
-:cve:`YYYY-XXXXX`: TODO
+:cve:`2026-55798`: WindowsViewer.get_command injection
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+If an attacker has control over the path passed to
+``ImageShow.WindowsViewer.get_command()``, and the result is executed by the user, the
+attacker may be able to execute arbitrary shell commands. Reported by Bin Luo,
+University of Electronic Science and Technology of China (luob87709@gmail.com).
+
+EPS image infinite loop
 ^^^^^^^^^^^^^^^^^^^^^^^
 
-TODO
+If a negative byte count is specified for the BeginBinary byte count, an infinite loop
+is possible as Pillow seeks repeatedly backwards. This value will now be validated.
+BeginBinary parsing was only added in Pillow 12.0.0. Reported by
+`jiagongzheng-stack <https://github.com/jiagongzheng-stack>`__.
+
+JPEG2000 image memory usage
+^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The total component width was incorrectly accumulated across tiles within a JPEG2000
+image, potentially leading to excessive memory use. This was introduced as part of an
+earlier security fix in Pillow 8.2.0, but has now been fixed. Reported by Fr3v1.
+
+McIdas out-of-bounds (OOB) read
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+McIdas images can specify the stride, and if incorrectly set, may cause an OOB read.
+This has been fixed. Reported by Devansh Shah, RUDRA Cybersecurity Pvt. Ltd.
 
-Backwards incompatible changes
-==============================
+Out-of-bounds (OOB) read when saving 1 mode TGA images
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-TODO
-^^^^
+Saving 1 mode images as TGA with run-length encoding can trigger an OOB read. This was
+added in Pillow 5.2.0, but the functionality is not possible under the TGA
+specification, so it has been removed. Reported by
+`Seratov <https://github.com/Seratov>`__.
 
-TODO
+Out-of-bounds (OOB) write from large RankFilter sizes
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+:py:class:`~PIL.ImageFilter.RankFilter`, and its subclasses, can potentially write
+out-of-bounds if given a large size. This has been fixed. Reported by
+`Seratov <https://github.com/Seratov>`__.
+
+Out-of-bounds (OOB) write from ``Image.paste()``
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-Deprecations
-============
+Large paste box dimensions can cause an OOB write in ``Image.crop()``,
+``Image.paste()`` and ``Image.alpha_composite()``. This has been fixed. Reported by
+`Seratov <https://github.com/Seratov>`__.
 
-TODO
-^^^^
+Out-of-bounds (OOB) write in ``ImageCmsTransform``
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-TODO
+Apply a transform mode to a different image mode can trigger an OOB write in
+``ImageCmsTransform``. Errors are now raised if the mode does not match. Reported by
+`Seratov <https://github.com/Seratov>`__.
 
-API changes
-===========
+:cve:`2026-54059`, :cve:`2026-54060`, :cve:`2026-55379`: Prevent FontFile decompression bomb
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-TODO
-^^^^
+Decompression bomb checks have now been added to :py:class:`~PIL.FontFile.FontFile`,
+and its subclasses, checking the width and height of characters. Reported by Rahul
+Singh and Dinesh.
 
-TODO
+:cve:`2026-55380`: Prevent GD decompression bomb
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+A decompression bomb check has been added to :py:class:`~PIL.GdImageFile.GdImageFile`.
+This is format must be explicitly called though, rather than being accessible from
+``Image.open()``. Reported by Rahul Singh.
 
 API additions
 =============
@@ -51,6 +96,12 @@ default, images will be captured at 2x. If ``scale_down`` is ``True``, they will
 
 Previously, macOS screenshots with a ``bbox`` were captured at 1x by default.
 
+Added ``max_length`` argument to ``PdfStream.decode()``
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+When calling ``PdfStream.decode()``, the maximum length of data to decode can now be
+specified. This will default to ``ImageFile.SAFEBLOCK``.
+
 Other changes
 =============