Avoiding ReDoS attacks used in user-facing, regex-related REST endpoints.#26483
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…ex-related REST endpoints. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
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janheise
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| @Override | ||
| public char charAt(final int index) { | ||
| if (clock.millis() > deadline) { | ||
| throw new TimeoutException(); |
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Should we use java.util.concurrent.TimeoutException here?
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java.util.concurrent.TimeoutException is a checked exception
I cannot change the signature of charAt() method while overriding
| safePattern.compile(regex); | ||
| response.isValid(true); | ||
| } catch (PatternSyntaxException e) { | ||
| } catch (IllegalArgumentException e) { |
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What about the PatternSyntaxException, where is it handled now?
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PatternSyntaxException is a sub-class of IllegalArgumentException...
dennisoelkers
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Code looks good, tested before and after:
Before:
$ curl -XPOST -H 'X-Requested-by: ReDoS' -u admin:admin -d '{ "string": "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa!", "regex": "(.*a){20}$" }' -H 'Content-Type: application/json' http://localhost:8080/api/tools/regex_tester
[hangs]
After:
$ curl -XPOST -H 'X-Requested-by: ReDoS' -u admin:admin -d '{ "string": "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa!", "regex": "(.*a){20}$" }' -H 'Content-Type: application/json' http://localhost:8080/api/tools/regex_tester
{"type":"ApiError","message":"Regular expression matching timed out — the pattern may be susceptible to catastrophic backtracking"}%
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…nts. (#26483) (#26535) * SafePattern class for avoiding ReDoS attacks used in user-facing, regex-related REST endpoints. * Changelog added * An attempt to replace System.currentTimeMillis() with Clock. * Removing length limits for input and regexp --------- (cherry picked from commit 5a8de34) Co-authored-by: Łukasz Kamiński <lukasz.kaminski@graylog.com> Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>
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Description
SafePattern class for avoiding ReDoS attacks used in user-facing, regex-related REST endpoints.
Motivation and Context
Protect against those types of attacks from malicious users.
How Has This Been Tested?
Manually and with new unit tests.
Types of changes
Checklist: