Description
Text::CSV_XS versions before 1.65 for Perl read before the start of an all-blank field under allow_whitespace in strip_trail_whitespace. Under allow_whitespace, strip_trail_whitespace removes trailing spaces and tabs from each unquoted field without stopping at the start of the field. For a field of only blanks it reads the byte before the field's heap buffer. If that byte is also a space or tab, it may be zeroed and the walk continue backwards, depending on what the allocator placed there. Leading blanks are normally skipped before a field is stored, but an all-blank field still arrives after a leading escape_char that differs from quote_char, or as a quoted field in getline when its line ends in two CRs.
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:H/I:N/A:N - EPSS — exploit probability
- 0% percentile: 29 · as of 10 November 2026
- CWE
- CWE-127
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