Pypdf Project Pypdf vulnerabilities

CVE-2026-41312 [MEDIUM] CWE-789 CVE-2026-41312: pypdf is a free and open-source pure-python PDF library. An attacker who uses a vulnerability presen pypdf is a free and open-source pure-python PDF library. An attacker who uses a vulnerability present in versions prior to 6.10.2 can craft a PDF which leads to the RAM being exhausted. This requires accessing a stream compressed using `/FlateDecode` with a `/Predictor` unequal 1 and large predictor parameters. This has been fixed in pypdf 6.10.2. A

CVE-2026-41314 [MEDIUM] CWE-789 CVE-2026-41314: pypdf is a free and open-source pure-python PDF library. An attacker who uses a vulnerability presen pypdf is a free and open-source pure-python PDF library. An attacker who uses a vulnerability present in versions prior to 6.10.2 can craft a PDF which leads to the RAM being exhausted. This requires accessing an image using `/FlateDecode` with large size values. This has been fixed in pypdf 6.10.2. As a workaround, one may apply the changes from th

CVE-2026-115585 [HIGH] CWE-400 pypdf: Possible long runtimes for repeated malformed cross-reference entries (Follow-up) pypdf: Possible long runtimes for repeated malformed cross-reference entries (Follow-up) ### 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==6.21.2](https://github.com/py-pdf/pypdf/releases/tag/6.21.2)

CVE-2026-57204 [MEDIUM] CWE-400 CVE-2026-57204: pypdf is a free and open-source pure-python PDF library. Prior to 6.13.3, a maliciously crafted PDF 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 MAX_DECLARED_STREAM_LENGTH is sometimes ignored. This requires parsing a content stream without a /Length value. This issue has been fixed in v

CVE-2026-33123 [MEDIUM] CWE-400 CVE-2026-33123: pypdf is a free and open-source pure-python PDF library. Versions prior to 6.9.1 allow an attacker t pypdf is a free and open-source pure-python PDF library. Versions prior to 6.9.1 allow an attacker to craft a malicious PDF which leads to long runtimes and/or large memory usage. Exploitation requires accessing an array-based stream with many entries. This issue has been fixed in version 6.9.1.

CVE-2026-41313 [MEDIUM] CWE-834 CVE-2026-41313: pypdf is a free and open-source pure-python PDF library. An attacker who uses a vulnerability presen pypdf is a free and open-source pure-python PDF library. An attacker who uses a vulnerability present in versions prior to 6.10.2 can craft a PDF which leads to long runtimes. This requires loading a PDF with a large trailer `/Size` value in incremental mode. This has been fixed in pypdf 6.10.2. As a workaround, one may apply the changes from the pa

CVE-2026-113792 [MEDIUM] CWE-835 pypdf: Possible infinite loop in PdfWriter.find_outline_item pypdf: Possible infinite loop in PdfWriter.find_outline_item ### Impact An attacker who uses this vulnerability can craft a PDF which leads to an infinite loop. This requires calling `find_outline_item` on a `PdfWriter`. ### Patches This has been fixed in [pypdf==6.20.1](https://github.com/py-pdf/pypdf/releases/tag/6.20.1). ### Workarounds If you cannot upgrade yet, consider applying the changes f

CVE-2026-113794 [MEDIUM] CWE-835 pypdf: Possible infinite loop when hitting EOF in standard xref table pypdf: Possible infinite loop when hitting EOF in standard xref table ### Impact An attacker who uses this vulnerability can craft a PDF which leads to an infinite loop. This requires an incomplete file which ends inside the xref table. ### Patches This has been fixed in [pypdf==6.20.0](https://github.com/py-pdf/pypdf/releases/tag/6.20.0). ### Workarounds If you cannot upgrade yet, consid

CVE-2023-36810 [MEDIUM] CWE-407 CVE-2023-36810: pypdf is a pure-python PDF library capable of splitting, merging, cropping, and transforming the pag pypdf is a pure-python PDF library capable of splitting, merging, cropping, and transforming the pages of PDF files. An attacker who uses this vulnerability can craft a PDF which leads to unexpected long runtime. This quadratic runtime blocks the current process and can utilize a single core of the CPU by 100%. It does not affect memory usage. This

CVE-2026-113795 [MEDIUM] CWE-400 pypdf: Possible large memory usage for streams with multiple filters pypdf: Possible large memory usage for streams with multiple filters ### Impact An attacker who uses this vulnerability can craft a PDF which leads to large memory consumption. This requires accessing any stream with a large amount of filters or multiple filters which pass around large amounts of data. ### Patches This has been fixed in [pypdf==6.20.0](https://github.com/py-pdf/pypdf/release

CVE-2026-113793 [MEDIUM] CWE-835 pypdf: Possible infinite loop when removing tree items pypdf: Possible infinite loop when removing tree items ### Impact An attacker who uses this vulnerability can craft a PDF which leads to an infinite loop. This requires removing an object from a tree, for example an outline item. ### Patches This has been fixed in [pypdf==6.20.1](https://github.com/py-pdf/pypdf/releases/tag/6.20.1). ### Workarounds If you cannot upgrade yet, consider applying the change

CVE-2026-22690 [MEDIUM] CWE-400 CVE-2026-22690: pypdf is a free and open-source pure-python PDF library. Prior to version 6.6.0, pypdf has possible pypdf is a free and open-source pure-python PDF library. Prior to version 6.6.0, pypdf has possible long runtimes for missing /Root object with large /Size values. An attacker who uses this vulnerability can craft a PDF which leads to possibly long runtimes for actually invalid files. This can be achieved by omitting the /Root entry in the trailer, w

CVE-2026-113790 [MEDIUM] CWE-400 pypdf: Possible large memory usage when parsing arrays and dictionaries pypdf: Possible large memory usage when parsing arrays and dictionaries ### Impact An attacker who uses this vulnerability can craft a PDF which leads to large memory usage. This requires parsing arrays and/or dictionaries with lots of elements. ### Patches This has been fixed in [pypdf==6.21.0](https://github.com/py-pdf/pypdf/releases/tag/6.21.0). ### Workarounds If you cannot upgrade

CVE-2026-113789 [MEDIUM] CWE-400 pypdf: Possible long runtimes/large memory usage when retrieving form fields pypdf: Possible long runtimes/large memory usage when retrieving form fields ### Impact An attacker who uses this vulnerability can craft a PDF which leads to large memory usage and/or long runtimes. This requires retrieving the form fields of a document. ### Patches This has been fixed in [pypdf==6.21.0](https://github.com/py-pdf/pypdf/releases/tag/6.21.0). ### Workarounds If you

CVE-2026-113791 [MEDIUM] CWE-400 pypdf: Possible large memory usage when parsing content streams pypdf: Possible large memory usage when parsing content streams ### Impact An attacker who uses this vulnerability can craft a PDF which leads to large memory usage. This requires parsing content streams with many small operations. ### Patches This has been fixed in [pypdf==6.21.0](https://github.com/py-pdf/pypdf/releases/tag/6.21.0). ### Workarounds If you cannot upgrade yet, consider applying

CVE-2023-36807 [MEDIUM] CWE-835 CVE-2023-36807: pypdf is a pure-python PDF library capable of splitting, merging, cropping, and transforming the pag pypdf is a pure-python PDF library capable of splitting, merging, cropping, and transforming the pages of PDF files. In version 2.10.5 an attacker who uses this vulnerability can craft a PDF which leads to an infinite loop. This infinite loop blocks the current process and can utilize a single core of the CPU by 100%. It does not affect memory usage

CVE-2026-82398 [MEDIUM] CWE-407 CVE-2026-82398: pypdf is a free and open-source pure-python PDF library. Prior to 6.15.0, an attacker can craft a PD pypdf is a free and open-source pure-python PDF library. Prior to 6.15.0, an attacker can craft a PDF that causes long runtimes when the pypdf/_utils.py function read_until_whitespace reads a stream containing a long run of bytes without whitespace. The function repeatedly performs immutable bytes concatenation in a one-byte loop, causing quadratic

CVE-2026-22691 [MEDIUM] CWE-400 CVE-2026-22691: pypdf is a free and open-source pure-python PDF library. Prior to version 6.6.0, pypdf has possible pypdf is a free and open-source pure-python PDF library. Prior to version 6.6.0, pypdf has possible long runtimes for malformed startxref. An attacker who uses this vulnerability can craft a PDF which leads to possibly long runtimes for invalid startxref entries. When rebuilding the cross-reference table, PDF files with lots of whitespace characters

CVE-2026-28804 [MEDIUM] CWE-407 CVE-2026-28804: pypdf is a free and open-source pure-python PDF library. Prior to version 6.7.5, an attacker who use pypdf is a free and open-source pure-python PDF library. Prior to version 6.7.5, an attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires accessing a stream which uses the /ASCIIHexDecode filter. This issue has been patched in version 6.7.5.

CVE-2026-41168 [MEDIUM] CWE-834 CVE-2026-41168: pypdf is a free and open-source pure-python PDF library. An attacker who uses a vulnerability presen pypdf is a free and open-source pure-python PDF library. An attacker who uses a vulnerability present in versions prior to 6.10.1 can craft a PDF which leads to long runtimes. This requires cross-reference streams with wrong large `/Size` values or object streams with wrong large `/N` values. This has been fixed in pypdf 6.10.1. As a workaround, one