CVE-2026-53424

CRITICALPre-NVD 9.19.1—
EchelonGraph scoreMEDIUM confidence

This critical-severity CVE scores 9.1 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.6% (46th percentile of EPSS-scored CVEs). GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
Trending — 3 sources updated this week
9.1EG
EchelonGraph verdictPlan mitigationSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0.6%CVSS: 9.1Exploit: None knownExposed services: Not assessed

No fix is confirmed yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for the fix.

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.

CVSS v3
9.1
EG Score
9.1CRITICALmedium confidence
EG Risk
56
EG Risk 56/100CISA SSVC

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity91% × 45%
Exploitation1% × 40%
Automatability100% × 15%
CISA SSVC: Track at low or medium mission impact; Attend at high (mission-essential systems).
Action: No fix is confirmed yet. Restrict network exposure of the affected system or apply the vendor's mitigation within your standard update timelines at low or medium mission impact and sooner than that at high, and watch the vendor's advisory for the fix.
EPSS PROB
0.6%
EPSS %ILE
46th
KEV
Not listed

CISA SSVCTrack at low or medium mission impact; Attend at high (mission-essential systems).

No fix is confirmed yet. Restrict network exposure of the affected system or apply the vendor's mitigation within your standard update timelines at low or medium mission impact and sooner than that at high, and watch the vendor's advisory for the fix.

Exploitation none (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). Mission impact is CISA's Mission & Well-being decision point, and only you can judge it: high means the affected system is essential to your organisation's mission, or its compromise could cause irreversible harm to people. CISA's decision table

Published

August 20, 2026

Last Modified

August 24, 2026

Advisory Details (2)

Auto-updated Sep 15, 2026
No patch confirmed yet.

Vendor Advisories for CVE-2026-53424(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Affected Packages

(1 across 1 ecosystem)
Hex(1)
PackageVulnerable rangeFix by version rangeDependents
samly0.10.0 ... 1.4.0 (27 versions)
  • 0.3.0 on: no fix on record
—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 43× in last 7d / 188× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

Showing the most recent 100 of 310 total refreshes for this CVE.

  1. 2026-10-05 10:21 UTCGHSA enrichment
  2. 2026-10-05 05:58 UTCGHSA enrichment
  3. 2026-10-05 01:35 UTCEG score recompute
  4. 2026-10-05 01:35 UTCGHSA enrichment
  5. 2026-10-04 23:22 UTCEPSS rescore
  6. 2026-10-04 20:52 UTCGHSA enrichment
  7. 2026-10-04 15:47 UTCGHSA enrichment
  8. 2026-10-04 11:25 UTCGHSA enrichment
  9. 2026-10-04 07:01 UTCGHSA enrichment
  10. 2026-10-04 02:39 UTCGHSA enrichment
  11. 2026-10-03 21:10 UTCGHSA enrichment
  12. 2026-10-03 16:47 UTCEG score recompute
  13. 2026-10-03 16:47 UTCGHSA enrichment
  14. 2026-10-03 14:26 UTCEPSS rescore
  15. 2026-10-03 06:52 UTCGHSA enrichment
  16. 2026-10-03 02:29 UTCGHSA enrichment
  17. 2026-10-02 21:55 UTCEG score recompute
  18. 2026-10-02 21:55 UTCGHSA enrichment
  19. 2026-10-02 17:56 UTCEPSS rescore
  20. 2026-10-02 17:32 UTCGHSA enrichment
  21. 2026-10-02 12:55 UTCGHSA enrichment
  22. 2026-10-02 06:49 UTCGHSA enrichment
  23. 2026-10-02 01:55 UTCGHSA enrichment
  24. 2026-10-01 21:29 UTCEG score recompute
  25. 2026-10-01 21:29 UTCGHSA enrichment
Show 75 more
  1. 2026-10-01 19:50 UTCEPSS rescore
  2. 2026-10-01 14:27 UTCGHSA enrichment
  3. 2026-10-01 10:04 UTCGHSA enrichment
  4. 2026-10-01 05:41 UTCGHSA enrichment
  5. 2026-10-01 01:13 UTCGHSA enrichment
  6. 2026-09-30 20:31 UTCEG score recompute
  7. 2026-09-30 20:31 UTCGHSA enrichment
  8. 2026-09-30 15:03 UTCEPSS rescore
  9. 2026-09-30 08:13 UTCEG score recompute
  10. 2026-09-30 08:13 UTCGHSA enrichment
  11. 2026-09-29 15:22 UTCEPSS rescore
  12. 2026-09-29 06:23 UTCGHSA enrichment
  13. 2026-09-29 02:00 UTCGHSA enrichment
  14. 2026-09-28 21:38 UTCEG score recompute
  15. 2026-09-28 21:38 UTCGHSA enrichment
  16. 2026-09-28 14:21 UTCEG score recompute
  17. 2026-09-28 14:21 UTCGHSA enrichment
  18. 2026-09-28 13:51 UTCEPSS rescore
  19. 2026-09-28 09:58 UTCGHSA enrichment
  20. 2026-09-28 05:36 UTCGHSA enrichment
  21. 2026-09-28 01:13 UTCGHSA enrichment
  22. 2026-09-27 20:50 UTCGHSA enrichment
  23. 2026-09-27 16:27 UTCEG score recompute
  24. 2026-09-27 16:27 UTCGHSA enrichment
  25. 2026-09-27 13:48 UTCEPSS rescore
  26. 2026-09-27 12:04 UTCGHSA enrichment
  27. 2026-09-27 07:35 UTCGHSA enrichment
  28. 2026-09-27 03:02 UTCEG score recompute
  29. 2026-09-27 03:02 UTCGHSA enrichment
  30. 2026-09-26 15:59 UTCEPSS rescore
  31. 2026-09-25 09:26 UTCGHSA enrichment
  32. 2026-09-25 05:04 UTCGHSA enrichment
  33. 2026-09-25 00:41 UTCGHSA enrichment
  34. 2026-09-24 19:08 UTCEG score recompute
  35. 2026-09-24 19:08 UTCGHSA enrichment
  36. 2026-09-24 14:04 UTCEPSS rescore
  37. 2026-09-24 13:36 UTCGHSA enrichment
  38. 2026-09-24 09:13 UTCGHSA enrichment
  39. 2026-09-24 04:50 UTCGHSA enrichment
  40. 2026-09-24 00:27 UTCGHSA enrichment
  41. 2026-09-23 20:05 UTCEG score recompute
  42. 2026-09-23 20:05 UTCGHSA enrichment
  43. 2026-09-23 17:54 UTCEPSS rescore
  44. 2026-09-23 13:50 UTCGHSA enrichment
  45. 2026-09-23 09:27 UTCGHSA enrichment
  46. 2026-09-23 05:04 UTCGHSA enrichment
  47. 2026-09-23 00:41 UTCGHSA enrichment
  48. 2026-09-22 20:18 UTCGHSA enrichment
  49. 2026-09-22 15:51 UTCEG score recompute
  50. 2026-09-22 15:51 UTCGHSA enrichment
  51. 2026-09-22 11:29 UTCGHSA enrichment
  52. 2026-09-22 07:06 UTCGHSA enrichment
  53. 2026-09-22 02:43 UTCGHSA enrichment
  54. 2026-09-21 22:18 UTCEG score recompute
  55. 2026-09-21 22:17 UTCGHSA enrichment
  56. 2026-09-21 17:53 UTCGHSA enrichment
  57. 2026-09-21 12:13 UTCGHSA enrichment
  58. 2026-09-21 07:50 UTCGHSA enrichment
  59. 2026-09-21 02:42 UTCGHSA enrichment
  60. 2026-09-20 22:19 UTCEG score recompute
  61. 2026-09-20 22:19 UTCGHSA enrichment
  62. 2026-09-20 20:16 UTCEPSS rescore
  63. 2026-09-20 17:55 UTCGHSA enrichment
  64. 2026-09-20 13:31 UTCGHSA enrichment
  65. 2026-09-20 09:01 UTCGHSA enrichment
  66. 2026-09-20 01:59 UTCGHSA enrichment
  67. 2026-09-19 21:36 UTCGHSA enrichment
  68. 2026-09-19 17:13 UTCEG score recompute
  69. 2026-09-19 17:13 UTCGHSA enrichment
  70. 2026-09-19 12:49 UTCGHSA enrichment
  71. 2026-09-19 08:26 UTCGHSA enrichment
  72. 2026-09-19 04:03 UTCGHSA enrichment
  73. 2026-09-18 23:39 UTCEG score recompute
  74. 2026-09-18 23:39 UTCGHSA enrichment
  75. 2026-09-18 19:28 UTCEPSS rescore

Frequently asked(5)

What is CVE-2026-53424?
CVE-2026-53424 is a critical vulnerability published on August 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.decodeidpauthresp/3 in lib/samly/helper.ex calls esamlsp:validate_assertion/2, whose default duplicate detector is a…
When was CVE-2026-53424 disclosed?
CVE-2026-53424 was first published on August 20, 2026, with the most recent update on August 24, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-53424 actively exploited?
CVE-2026-53424 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.6% probability of exploitation in the next 30 days (46th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-53424?
CVE-2026-53424 has a CVSS base score of 9.1 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-53424?
No fix for CVE-2026-53424 is confirmed yet. Until one is published, restrict network exposure of the affected system or apply the vendor's mitigation — for example, keep it off the internet or limit it to trusted networks — and watch the vendor's advisory for the fix. The vendor advisories EchelonGraph has for CVE-2026-53424 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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