Security: Regex with greedy quantifier on untrusted input#630
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barttran2k wants to merge 1 commit intooffa:masterfrom
Open
Security: Regex with greedy quantifier on untrusted input#630barttran2k wants to merge 1 commit intooffa:masterfrom
barttran2k wants to merge 1 commit intooffa:masterfrom
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The regex `(?<=\[\*\*).*(?=\*\*\])` in `add_app()` uses `.*` (greedy match) between a lookbehind and lookahead. While not a severe ReDoS risk in this specific pattern, applying it to user-contributed markdown lines (from README.md) with crafted input containing many `**]` sequences could cause slower-than-expected matching. This is a minor concern given the input source. Affected files: ensure_sorted.py Signed-off-by: Trần Bách <45133811+barttran2k@users.noreply.github.com>
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Problem
The regex
(?<=\[\*\*).*(?=\*\*\])inadd_app()uses.*(greedy match) between a lookbehind and lookahead. While not a severe ReDoS risk in this specific pattern, applying it to user-contributed markdown lines (from README.md) with crafted input containing many**]sequences could cause slower-than-expected matching. This is a minor concern given the input source.Severity:
lowFile:
ensure_sorted.pySolution
Use a non-greedy quantifier
.*?or a more specific character class like[^*]+to avoid unnecessary backtracking:re.findall(r'(?<=\[\*\*)[^*]+(?=\*\*\])', app_str)Changes
ensure_sorted.py(modified)Testing