Impact
An attacker who uses this vulnerability can craft a PDF which leads to large memory usage. This requires loading an invalid dictionary.
Patches
This has been fixed in pypdf==6.21.3.
Workarounds
If you cannot upgrade yet, consider applying the changes from PR #4265.
Impact
An attacker who uses this vulnerability can craft a PDF which leads to an infinite loop. This requires opening an incomplete file without a trailer.
Patches
This has been fixed in pypdf==6.21.4.
Workarounds
If you cannot upgrade yet, consider applying the changes from PR #4289.
Impact
An attacker who uses this vulnerability can craft a PDF which leads to an infinite loop. This requires cloning/duplicating a DictionaryObject.
Patches
This has been fixed in pypdf==6.21.4.
Workarounds
If you cannot upgrade yet, consider applying the changes from PR #4288.
Impact
An attacker who uses this vulnerability can craft a PDF which leads to large memory usage. This requires parsing the page tree with many shared resources.
Patches
This has been fixed in pypdf==6.21.4.
Workarounds
If you cannot upgrade yet, consider applying the changes from PR #4290.
Impact
An attacker who uses this vulnerability can craft a PDF which leads to large runtimes. This requires retrieving the page labels of a file.
Patches
This has been fixed in pypdf==6.21.3.
Workarounds
If you cannot upgrade yet, consider applying the changes from PR #4251.
Impact
An attacker who uses this vulnerability can craft a PDF which leads to large memory usage. This requires opening a file with cross-reference streams.
Patches
This has been fixed in pypdf==6.21.3.
Workarounds
If you cannot upgrade yet, consider applying the changes from PR #4269.
Impact
An attacker who uses this vulnerability can craft a PDF which leads to large runtimes/memory usage. This requires accessing the page count of an encrypted PDF file, which itself declares a wrong /Count value.
Patches
This has been fixed in pypdf==6.21.3.
Workarounds
If you cannot upgrade yet, consider applying the changes from PR #4270.
pypdf is an open source, pure-python PDF library. In affected versions an attacker may craft a PDF which leads to an infinite loop if parsecontentstream is executed. That is, for example, the case if the user extracted text from such a PDF. This issue was introduced in pull request #969 and resolved in pull request #1828. Users are advised to upgrade. Users unable to upgrade may modify the line while peek not in (b"\r", b"\n") in pypdf/generic/datastructures.py to while peek not in (b"\r", b"\n", b"").
Impact An attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires a call to readuntilwhitespace with an input which does not have whitespace for a long time.
Patches This has been fixed in pypdf==6.15.0.
Workarounds If you cannot upgrade yet, consider applying the changes from PR #3947.
Impact
An attacker who uses this vulnerability can craft a PDF which leads to an infinite loop. This requires a (usually writing) code path where TreeObject.insertchild is involved.
Patches
This has been fixed in pypdf==6.16.0.
Workarounds
If you cannot upgrade yet, consider applying the changes from PR #3964.
Impact
An attacker who uses this vulnerability can craft a PDF which leads to long runtimes and large memory consumption. This requires accessing the outlines of a document with either lots of entries or nested outlines with long re-used nesting paths.
Patches
This has been fixed in pypdf==6.16.1.
Workarounds
If you cannot upgrade yet, consider applying the changes from PR #3966.
Impact
An attacker who uses this vulnerability can craft a PDF which leads to long runtimes and large memory consumption. This requires extracting the text of a page with lots of XForm objects, where some of them might be re-used.
Patches
This has been fixed in pypdf==6.16.1.
Workarounds
If you cannot upgrade yet, consider applying the changes from PR #3966.
Impact
An attacker who uses this vulnerability can craft a PDF which leads to long runtimes and large memory consumption. This requires parsing the font width entries of a font with unusually large values, for example during text extraction.
Patches
This has been fixed in pypdf==6.15.0.
Workarounds
If you cannot upgrade yet, consider applying the changes from PR #3946.
Impact
An attacker who uses this vulnerability can craft a PDF which leads to large memory consumption. This requires parsing the /ToUnicode entry of a font with unusually large values, for example during text extraction.
Patches
This has been fixed in pypdf==6.15.0.
Workarounds
If you cannot upgrade yet, consider applying the changes from PR #3944.
Impact
An attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires cross-reference streams with repeated malformed cross-reference streams.
Patches
This has been fixed in pypdf==6.14.0.
Workarounds
If you cannot upgrade yet, consider applying the changes from PR #3887.
Impact
An attacker who uses this vulnerability can craft a PDF which leads to an infinite loop. This requires parsing the content stream of a page with a not terminated inline image, as done when extracting the page text for example.
Patches
This has been fixed in pypdf==6.14.1.
Workarounds
If you cannot upgrade yet, consider applying the changes from PR #3891.
Impact
An attacker who uses this vulnerability can craft a PDF which leads to large memory usage. This requires loading images where the declared size values are much too large compared to the actual data.
Patches
This has been fixed in pypdf==6.14.0.
Workarounds
If you cannot upgrade yet, consider applying the changes from PR #3888.
Impact
An attacker who uses this vulnerability can craft a PDF which leads to an infinite loop. This requires parsing the content stream of a page with a not terminated inline image, as done when extracting the page text for example. It only affects the ASCII85 and ASCIIHex filters.
Patches
This has been fixed in pypdf==6.14.2.
Workarounds
If you cannot upgrade yet, consider applying the changes from PR #3892.
pypdf is a free and open-source pure-python PDF library. Prior to 6.13.3, a maliciously crafted PDF can cause DoS. An attacker who uses this vulnerability can craft a PDF which leads to large memory usage, as MAXDECLAREDSTREAMLENGTH is sometimes ignored. This requires parsing a content stream without a /Length value. This issue has been fixed in version 6.13.3.
Impact
An attacker who uses this vulnerability can craft a PDF which leads to an infinite loop. This requires merging a file with threads/articles into a writer.
Patches
This has been fixed in pypdf==6.13.1.
Workarounds
If users cannot upgrade yet, consider applying the changes from PR #3839.
Impact
An attacker who uses this vulnerability can craft a PDF which leads to an infinite loop. This requires merging a file with outlines into a writer.
Patches
This has been fixed in pypdf==6.13.0.
Workarounds
If you cannot upgrade yet, consider applying the changes from PR #3830.
Impact
An attacker who uses this vulnerability can craft a PDF which leads to an infinite loop. This requires extracting the text in layout mode.
Patches
This has been fixed in pypdf==6.13.0.
Workarounds
If you cannot upgrade yet, consider applying the changes from PR #3830.
Impact
An attacker who uses this vulnerability can craft a PDF which leads to large memory usage. This requires parsing large XMP metadata, possibly with lots of unnecessary elements.
Patches This has been fixed in pypdf==6.12.1.
Workarounds If you cannot upgrade yet, consider applying the changes from PR #3796.
Impact An attacker who uses this vulnerability can craft a PDF which leads to large memory usage. This requires extracting the text of a page which contains a form XObject with self-references.
Patches This has been fixed in pypdf==6.12.2.
Workarounds If you cannot upgrade yet, consider applying the changes from PR #3805.
Impact
An attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires cross-reference streams with /W [0 0 0] values and large /Size values.
Patches
This has been fixed in pypdf==6.12.0.
Workarounds
If developers are unable to upgrade their apps immediately, they should consider applying the changes from PR #3791.
Impact An attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires accessing a stream which uses the /FlateDecode filter with a PNG predictor.
Patches This has been fixed in pypdf==6.12.2.
Workarounds If you cannot upgrade yet, consider applying the changes from PR #3806.
Impact
An attacker who uses this vulnerability can craft a PDF which leads to large memory usage. This requires extracting text in layout mode with large character offsets.
Patches
This has been fixed in pypdf==6.12.0.
Workarounds
If developers are unable to immediately upgrade, they should consider applying the changes from PR #3790.
Impact
An attacker who uses this vulnerability can craft a PDF which leads to large memory usage. This requires parsing the XMP metadata.
Patches This has been fixed in pypdf==6.10.0.
Workarounds If you cannot upgrade yet, consider applying the changes from PR #3724.
Impact
An attacker who uses this vulnerability can craft a PDF which leads to large memory usage. This requires parsing a content stream with a rather large /Length value, regardless of the actual data length inside the stream.
Patches This has been fixed in pypdf==6.8.0.
Workarounds If you cannot upgrade yet, consider applying the changes from PR #3675.
As far as we are aware, this mostly affects reading from buffers of unknown size, as returned by open("file.pdf", mode="rb") for example. Passing a file path or a BytesIO buffer to pypdf instead does not seem to trigger the vulnerability.
Impact An attacker who uses this vulnerability can craft a PDF which leads to long runtimes and/or large memory usage. This requires accessing an array-based stream with lots of entries.
Patches This has been fixed in pypdf==6.9.1.
Workarounds If you cannot upgrade yet, consider applying the changes from PR #3686.