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[3.12] gh-135661: Fix CDATA section parsing in HTMLParser (GH-135665) #137774

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Merged
merged 1 commit into from
Oct 6, 2025
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[3.12] gh-135661: Fix CDATA section parsing in HTMLParser (GH-135665) #137774

merged 1 commit into from
Oct 6, 2025

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@serhiy-storchaka serhiy-storchaka commented Aug 14, 2025 •
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"] ]>" and "]] >" no longer end the CDATA section.

Make CDATA section parsing context depending.
Add private method HTMLParser._set_support_cdata() to change the context. If called with True, "<[CDATA[" starts a CDATA section which ends with "]]>". If called with False, "<[CDATA[" starts a bogus comments which ends with ">".

(cherry picked from commit 0cbbfc4)

@serhiy-storchaka serhiy-storchaka added needs backport to 3.9 only security fixes needs backport to 3.10 only security fixes needs backport to 3.11 only security fixes labels Aug 14, 2025
@bedevere-app bedevere-app bot mentioned this pull request Aug 14, 2025
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@bedevere-app bedevere-app bot added the type-security A security issue label Aug 14, 2025
@bedevere-app bedevere-app bot mentioned this pull request Aug 14, 2025
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Backports to 3.9-3.11 will be created from the 3.12 backport.

@serhiy-storchaka serhiy-storchaka added needs backport to 3.9 only security fixes needs backport to 3.10 only security fixes needs backport to 3.11 only security fixes and removed needs backport to 3.9 only security fixes needs backport to 3.10 only security fixes needs backport to 3.11 only security fixes labels Aug 14, 2025
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This code slightly differs from main. Unknown declarations (including CDATA) call handle_decl() instead of handle_comment() if they end with "]>". This is for larger compatibility with old code. But the first ">" ends them, according to the HTML specs.

@serhiy-storchaka
[3.12] pythongh-135661: Fix CDATA section parsing in HTMLParser (pyth…
1904262 
…onGH-135665)

"] ]>" and "]] >" no longer end the CDATA section.

Make CDATA section parsing  context depending.
Add private method HTMLParser._set_support_cdata() to change the context.
If called with True, "<[CDATA[" starts a CDATA section which ends with "]]>".
If called with False, "<[CDATA[" starts a bogus comments which ends with ">".
(cherry picked from commit 0cbbfc4)

Co-authored-by: Serhiy Storchaka <[email protected]>
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This includes also #137873.

@Yhg1s Yhg1s merged commit dcf2476 into python:3.12 Oct 6, 2025
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Thanks @serhiy-storchaka for the PR, and @Yhg1s for merging it 🌮🎉.. I'm working now to backport this PR to: 3.9, 3.10, 3.11.
🐍🍒⛏🤖

miss-islington pushed a commit to miss-islington/cpython that referenced this pull request Oct 6, 2025
@serhiy-storchaka @miss-islington
[3.12] pythongh-135661: Fix CDATA section parsing in HTMLParser (pyth…
03909c0 
…onGH-135665) (pythonGH-137774)

"] ]>" and "]] >" no longer end the CDATA section.

Make CDATA section parsing  context depending.
Add private method HTMLParser._set_support_cdata() to change the context.
If called with True, "<[CDATA[" starts a CDATA section which ends with "]]>".
If called with False, "<[CDATA[" starts a bogus comments which ends with ">".
(cherry picked from commit 0cbbfc4)
(cherry picked from commit dcf24768c918c41821cda6fe6a1aa20ce26545dd)

Co-authored-by: Serhiy Storchaka <[email protected]>
miss-islington pushed a commit to miss-islington/cpython that referenced this pull request Oct 6, 2025
@serhiy-storchaka @miss-islington
[3.12] pythongh-135661: Fix CDATA section parsing in HTMLParser (pyth…
e139cb3 
…onGH-135665) (pythonGH-137774)

"] ]>" and "]] >" no longer end the CDATA section.

Make CDATA section parsing  context depending.
Add private method HTMLParser._set_support_cdata() to change the context.
If called with True, "<[CDATA[" starts a CDATA section which ends with "]]>".
If called with False, "<[CDATA[" starts a bogus comments which ends with ">".
(cherry picked from commit 0cbbfc4)
(cherry picked from commit dcf2476)

Co-authored-by: Serhiy Storchaka <[email protected]>
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bedevere-app bot commented Oct 6, 2025

GH-139659 is a backport of this pull request to the 3.11 branch.

miss-islington pushed a commit to miss-islington/cpython that referenced this pull request Oct 6, 2025
@serhiy-storchaka @miss-islington
[3.12] pythongh-135661: Fix CDATA section parsing in HTMLParser (pyth…
8ab85ab 
…onGH-135665) (pythonGH-137774)

"] ]>" and "]] >" no longer end the CDATA section.

Make CDATA section parsing  context depending.
Add private method HTMLParser._set_support_cdata() to change the context.
If called with True, "<[CDATA[" starts a CDATA section which ends with "]]>".
If called with False, "<[CDATA[" starts a bogus comments which ends with ">".
(cherry picked from commit 0cbbfc4)
(cherry picked from commit dcf2476)

Co-authored-by: Serhiy Storchaka <[email protected]>
@bedevere-app bedevere-app bot removed the needs backport to 3.11 only security fixes label Oct 6, 2025
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bedevere-app bot commented Oct 6, 2025

GH-139660 is a backport of this pull request to the 3.10 branch.

@bedevere-app bedevere-app bot removed the needs backport to 3.10 only security fixes label Oct 6, 2025
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bedevere-app bot commented Oct 6, 2025

GH-139661 is a backport of this pull request to the 3.9 branch.

@bedevere-app bedevere-app bot removed the needs backport to 3.9 only security fixes label Oct 6, 2025
ambv pushed a commit that referenced this pull request Oct 7, 2025
@miss-islington @serhiy-storchaka
[3.11] gh-135661: Fix CDATA section parsing in HTMLParser (GH-135665) (…
22d5724 
…GH-137774) (GH-139659)

"] ]>" and "]] >" no longer end the CDATA section.

Make CDATA section parsing  context depending.
Add private method HTMLParser._set_support_cdata() to change the context.
If called with True, "<[CDATA[" starts a CDATA section which ends with "]]>".
If called with False, "<[CDATA[" starts a bogus comments which ends with ">".
(cherry picked from commit 0cbbfc4)
(cherry picked from commit dcf2476)

Co-authored-by: Serhiy Storchaka <[email protected]>
ambv pushed a commit that referenced this pull request Oct 7, 2025
@miss-islington @serhiy-storchaka
[3.10] gh-135661: Fix CDATA section parsing in HTMLParser (GH-135665) (…
7317e0b 
…GH-137774) (GH-139660)

"] ]>" and "]] >" no longer end the CDATA section.

Make CDATA section parsing  context depending.
Add private method HTMLParser._set_support_cdata() to change the context.
If called with True, "<[CDATA[" starts a CDATA section which ends with "]]>".
If called with False, "<[CDATA[" starts a bogus comments which ends with ">".
(cherry picked from commit 0cbbfc4)
(cherry picked from commit dcf2476)

Co-authored-by: Serhiy Storchaka <[email protected]>
ambv added a commit that referenced this pull request Oct 7, 2025
@miss-islington @serhiy-storchaka @ambv
[3.9] gh-135661: Fix CDATA section parsing in HTMLParser (GH-135665) (G…
ed904d5 
…H-137774) (GH-139661)

"] ]>" and "]] >" no longer end the CDATA section.

Make CDATA section parsing  context depending.
Add private method HTMLParser._set_support_cdata() to change the context.
If called with True, "<[CDATA[" starts a CDATA section which ends with "]]>".
If called with False, "<[CDATA[" starts a bogus comments which ends with ">".
(cherry picked from commit 0cbbfc4)
(cherry picked from commit dcf2476)

Co-authored-by: Serhiy Storchaka <[email protected]>
Co-authored-by: Łukasz Langa <[email protected]>
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