Description
Text::CSV_XS versions before 1.65 for Perl allow quadratic CPU use by copying the unparsed remainder per record of CR-only input in getline. With eol unset, the default, getline reads with Perl's default line separator, so input with CR-only line endings arrives as one chunk. After each record the parser copies the whole unparsed remainder into a new buffer, which the next call parses and copies again, so the work grows with the square of the input size. A reader with default options that is sent CSV with classic Mac line endings spends seconds of CPU time on a megabyte of input.
References2
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 35 · as of 10 November 2026
- CWE
- CWE-407
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