Add advisory for quick-xml: quadratic attribute duplicate-check (CPU DoS)#3020
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djc merged 1 commit intoJul 2, 2026
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…DoS) quick-xml < 0.41.0: the default duplicate-attribute-name check in the `Attributes` iterator scanned all previously seen names for every attribute, so a start tag with N distinct names cost O(N^2) byte comparisons -- a remote, unauthenticated CPU-exhaustion DoS on untrusted XML. Fixed in 0.41.0 (tafia/quick-xml#971). Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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This adds a RustSec advisory for quick-xml#969.
quick-xml< 0.41.00.41.0(released 2026-06-29)The default
with_checks(true)attribute iterator —BytesStart::attributes()/try_get_attribute, also reached internally byNsReader— checked each attribute name against every previously seen name with a linear scan, so a single start tag withNdistinct attribute names costO(N²)byte comparisons (measured, release: 80k ≈ 6 s, 800k ≈ 10 min). On untrusted XML this is a CPU-exhaustion denial of service; because the check is pure computation with no I/O, a consumer's read/request timeout cannot interrupt it. Fixed in 0.41.0 (tafia/quick-xml#971).Reported by me; the
quick-xmlmaintainer asked that I file the RustSec advisory. The ID is left as theRUSTSEC-0000-0000placeholder for assignment.🤖 Generated with Claude Code