[3.14] gh-145264: Do not ignore excess Base64 data after the first padded quad (GH-145267) by serhiy-storchaka · Pull Request #146326 · python/cpython

serhiy-storchaka

…rst padded quad (pythonGH-145267)

Base64 decoder (see binascii.a2b_base64(), base64.b64decode(), etc)
no longer ignores excess data after the first padded quad in non-strict
(default) mode.  Instead, in conformance with RFC 4648, it ignores the
pad character, "=", if it is present before the end of the encoded data.
(cherry picked from commit 4561f64)

Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>

This was referenced

Mar 23, 2026

miss-islington pushed a commit to miss-islington/cpython that referenced this pull request

Mar 23, 2026

…rst padded quad (pythonGH-145267) (pythonGH-146326)

Base64 decoder (see binascii.a2b_base64(), base64.b64decode(), etc)
no longer ignores excess data after the first padded quad in non-strict
(default) mode.  Instead, in conformance with RFC 4648, it ignores the
pad character, "=", if it is present before the end of the encoded data.
(cherry picked from commit 4561f64)
(cherry picked from commit e31c551)

Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>

ambv pushed a commit that referenced this pull request

Mar 23, 2026

…dded quad (GH-145267) (GH-146326) (GH-146348)

Base64 decoder (see binascii.a2b_base64(), base64.b64decode(), etc)
no longer ignores excess data after the first padded quad in non-strict
(default) mode.  Instead, in conformance with RFC 4648, it ignores the
pad character, "=", if it is present before the end of the encoded data.
(cherry picked from commit 4561f64)
(cherry picked from commit e31c551)

Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>