How many CVEs have patched _flatten?

3 published CVEs changed _flatten in py-pdf/pypdf, in 4 distinct patches totalling 11 changed lines, between 2026 and 2026.

What is the latest CVE that changed _flatten?

CVE-2026-41168 (pypdf has possible long runtimes for wrong size values in cross-reference and object streams), published 2026-04-22, changed lines 1169 to 1177 of pypdf/_doc_common.py.

How does _flatten compare to the rest of py-pdf/pypdf?

py-pdf/pypdf has 52 CVEs with a located fix in total; 3 of them changed _flatten.

What do the line numbers refer to?

Line numbers are in the fixed version of the file, as the upstream patch left it. A CVE whose fix was backported to several branches is listed once, with the lines from the upstream commit.

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_flatten

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Patched Functions
Py Pdf
Pypdf
_flatten

_flatten in py-pdf/pypdf: Patched by 3 CVEs

py-pdf/pypdf

Function

_flatten

Name: _flatten in py-pdf/pypdf: CVE fixes
Creator: RadicalNotion.AI
License: https://creativecommons.org/licenses/by-nc/4.0/

pypdf/_doc_common.py

Last patched April 22, 2026

CVEs

That changed this function

Distinct patches

Backports counted once

Lines changed

Added plus removed

2026

Years

By CVE publication date

Overview

_flatten in py-pdf/pypdf was changed by 3 published CVE fixes in 2026, in 4 distinct patches that added or removed 11 lines in total.

py-pdf/pypdf has 52 CVEs with a located fix in total, so 6% of them touched this function.

CVEs that patched it

Every published CVE whose fix changed _flatten, newest first, with the lines each fix touched.

On this page

Overview
CVEs that patched it
Other functions in these files
Other hotspots in the repository
FAQ
References

pypdf has possible long runtimes for wrong size values in cross-reference and object streams
CVE-2026-41168 · lines 1169–1177 · +2 −1 in 2 hunks
Medium · CVSS 6.9
EPSS 0.5%2026-04-22
pypdf has possible long runtimes for malformed startxref
CVE-2026-22691 · lines 1173–1177 · +4 −0
Low · CVSS 2.7
EPSS 0.4%2026-01-10
pypdf has possible long runtimes for missing /Root object with large /Size values
CVE-2026-22690 · lines 1173–1177 · +4 −0
Low · CVSS 2.7
EPSS 0.4%2026-01-10

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Other functions in these files

Functions in the same file that CVE fixes also changed.

1_get_outlinepypdf/_doc_common.py3 CVEs · 4 patches2026
2convert_to_intpypdf/_doc_common.py2 CVEs · 2 patches2026
3modification_date_rawpypdf/_doc_common.py2 CVEs · 2 patches2026
4_get_attachment_contentspypdf/_doc_common.py1 CVEs · 2 patches2026
5xfapypdf/_doc_common.py1 CVEs · 2 patches2026

Other hotspots in the repository

Functions in py-pdf/pypdf changed by the most CVE fixes.

decode5 CVEs · pypdf/filters.py _decompress_with_limit4 CVEs · pypdf/filters.py decompress3 CVEs · pypdf/filters.py _get_outline3 CVEs · pypdf/_doc_common.py _extract_text3 CVEs · pypdf/_page.py extract_xform_text3 CVEs · pypdf/_page.py

All patched functions in py-pdf/pypdf

Frequently asked questions

Common questions about CVE fixes to _flatten.

How many CVEs have patched _flatten?: 3 published CVEs changed _flatten in py-pdf/pypdf, in 4 distinct patches totalling 11 changed lines, between 2026 and 2026.
What is the latest CVE that changed _flatten?: CVE-2026-41168 (pypdf has possible long runtimes for wrong size values in cross-reference and object streams), published 2026-04-22, changed lines 1169 to 1177 of pypdf/_doc_common.py.
How does _flatten compare to the rest of py-pdf/pypdf?: py-pdf/pypdf has 52 CVEs with a located fix in total; 3 of them changed _flatten.
What do the line numbers refer to?: Line numbers are in the fixed version of the file, as the upstream patch left it. A CVE whose fix was backported to several branches is listed once, with the lines from the upstream commit.

References

pypdf/_doc_common.py on GitHub (opens in a new tab)
All patched functions in py-pdf/pypdf
Patched functions directory

Fix locations are computed by RadicalNotion.AI from the upstream patch diff of each CVE. CVE data is sourced from the CVE Program.

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