CVE-2023-46250Medium· 5.1▾ SunlitPossible Infinite Loop when PdfWriter(clone_from) is used with a PDF
▾ Sunlit zone — Low / medium · no exploitation signal
impact 28.1 · likelihood 0 · exploitation 0
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Exploit-prediction probability, daily snapshots since Jul 8.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via OSV
0.2%
Last analysed / modified upstream
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.
That is, for example, the case when the pypdf-user manipulates an incoming malicious PDF e.g. by merging it with another PDF or by adding annotations.
The issue was fixed with #2264
If you cannot update your version of pypdf, you should modify pypdf/generic/_data_structures.py just like #2264 did.
pypdf >= 3.7.0, < 3.17.0Upgrade to a patched release:
pypdf 3.17.0Connected by shared product, vendor, weakness, or advisory.
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