Mitigating PHP2Shell: Everything You Need to Know
Easily map the attack path and prioritize which CVEs are a threat to your organization
Miggo AIGenerate vendor-ready rules for the observed attack patterns, plus reasoning and safe deployment guidance
Miggo AIRoot Cause AnalysisThe vulnerability description clearly states that the issue is 'Possible large memory usage when retrieving Roman page labels' and that it 'requires accessing the page labels of a document with large Roman numerals.' The provided patch commit 89db7c4fe9315ecc964bfdf05a4e8c4b94175163 directly addresses this by modifying the number2uppercase_roman_numeral function in pypdf/_page_labels.py. The key change is the introduction of a MAXIMUM_ROMAN_NUMERAL constant and a check (if num > MAXIMUM_ROMAN_NUMERAL:) to prevent the conversion of numbers larger than 3999. Before this patch, there was no such limit, allowing for the creation of arbitrarily large Roman numeral strings, which would consume excessive memory. Therefore, the number2uppercase_roman_numeral function is the direct point of vulnerability as it lacked the necessary input validation to prevent resource exhaustion.
number2uppercase_roman_numeralpypdf/_page_labels.py
| Package Name | Ecosystem | Vulnerable Versions | First Patched Version |
|---|---|---|---|
| pypdf | pip | < 6.17.0 | 6.17.0 |