Answer in brief
CVE-2026-53424 records a Critical severity (CVSS 9.1) vulnerability in Missing one-time-use enforcement in Samly allows replay of SAML bearer assertions. The current sources do not mark it as known exploited. The current feed maps dropbox/dropbox/samly (generic), handnot2/handnot2/samly (generic), dropbox/samly (generic), dropbox/samly (generic) and additional mapped packages. Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 9.1. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps dropbox/dropbox/samly (generic), handnot2/handnot2/samly (generic), dropbox/samly (generic), dropbox/samly (generic) and additional mapped packages. Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| dropbox/dropbox/samlygeneric | >=8a5bb1b4a4753d05470da2036323477f63cfdf4c <* | * |
| handnot2/handnot2/samlygeneric | >=8a5bb1b4a4753d05470da2036323477f63cfdf4c <* | * |
| dropbox/samlygeneric | >=v0.3.0 <* | * |
| dropbox/samlygeneric | >=8a5bb1b4a4753d05470da2036323477f63cfdf4c <* | * |
| handnot2/samlygeneric | >=8a5bb1b4a4753d05470da2036323477f63cfdf4c <* | * |
| dropbox/samlygeneric | >=0.3.0 <* | * |
Published upstream
Aug 20, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 24, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 20, 2026
Authentication Bypass by Capture-replay vulnerability in dropbox samly allows an attacker to authenticate as the subject of a captured SAML assertion by resubmitting it. Samly.Helper.decode_idp_auth_resp/3 in lib/samly/helper.ex calls esaml_sp:validate_assertion/2, whose default duplicate detector is a no-op. The /3 arity accepting a DuplicateFun exists in esaml and implements the check, but Samly never calls it and offers no configuration to supply one, so the SAML 2.0 Web Browser SSO Profile requirement that a bearer assertion be used once is unenforced. An attacker holding a valid SAMLResponse obtained from the network, from browser history, or from logs can submit the identical bytes repeatedly until the assertion's NotOnOrAfter passes, each time establishing a session as the assertion's subject. This issue affects samly: from 0.3.0 onward.
Quoted source text, attributed separately from HOL analysis.