CVE-2026-56299

MEDIUMPre-NVD 5.35.3—
EchelonGraph scoreMEDIUM confidence

Score 5.3 from GitHub Security Advisory published 2026-06-21. a secondary CVSS source baseline 5.3; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 3 sources updated this week
5.3EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 1%CVSS: 5.3Exploit: None knownExposed: 0

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

Capgo before 12.128.2 contains an authentication bypass vulnerability in the /build/upload/:jobId/* endpoint that allows unauthenticated attackers to trigger consistent 500 errors. Remote attackers can send OPTIONS requests to bypass authentication middleware and invoke tusProxy logic with invalid credentials, enabling trivial request flooding and denial of service.

CVSS v3
5.3
EG Score
5.3(medium)
EG Risk
39(Track)
EG Risk 39/100SSVC: Track

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
Severity53% × 45%
Exploitation1% × 40%
Automatability100% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
1%
EPSS %ILE
49%
KEV
Not listed

Published

June 21, 2026

Last Modified

June 23, 2026

Advisory Details (2)

Auto-updated Jun 23, 2026
🔬 Proof of concept available. Patch available. Sources: github.
generic

Capgo - Denial of Service via Unauthenticated OPTIONS Request to /build/upload Endpoint | Advisories | VulnCheck

https://www.vulncheck.com/advisories/capgo-denial-of-service-via-unauthenticated-options-request-to-build-upload-endpoint
github Patch Available🟡 PoC Available

Unauthenticated OPTIONS to /build/upload/:jobId/* triggers consistent 500 (reliable external error/DoS vector) · Advisory · Cap-go/capgo · GitHub

https://github.com/Cap-go/capgo/security/advisories/GHSA-6c7m-4223-446j

Vendor Advisories for CVE-2026-56299(1)

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

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 12× in last 7d / 61× 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.

  1. 2026-07-29 01:27 UTCEG score recompute
  2. 2026-07-29 01:27 UTCGHSA enrichment
  3. 2026-07-28 15:37 UTCEPSS rescore
  4. 2026-07-27 18:00 UTCEG score recompute
  5. 2026-07-27 18:00 UTCGHSA enrichment
  6. 2026-07-26 16:18 UTCEG score recompute
  7. 2026-07-26 16:18 UTCGHSA enrichment
  8. 2026-07-26 14:54 UTCEPSS rescore
  9. 2026-07-25 14:18 UTCEPSS rescore
  10. 2026-07-24 14:18 UTCEPSS rescore
  11. 2026-07-23 14:18 UTCEPSS rescore
  12. 2026-07-23 03:20 UTCEG score recompute
  13. 2026-07-22 14:08 UTCEPSS rescore
  14. 2026-07-21 15:25 UTCEPSS rescore
  15. 2026-07-20 17:08 UTCEPSS rescore
  16. 2026-07-19 02:29 UTCEPSS rescore
  17. 2026-07-18 10:04 UTCEPSS rescore
  18. 2026-07-17 01:37 UTCGHSA enrichment
  19. 2026-07-16 17:03 UTCEPSS rescore
  20. 2026-07-16 01:15 UTCGHSA enrichment
  21. 2026-07-15 16:57 UTCEPSS rescore
  22. 2026-07-15 16:57 UTCEPSS rescore
  23. 2026-07-15 02:00 UTCEPSS rescore
  24. 2026-07-15 02:00 UTCEPSS rescore
  25. 2026-07-15 00:52 UTCGHSA enrichment
Show 57 more
  1. 2026-07-14 00:11 UTCGHSA enrichment
  2. 2026-07-13 22:31 UTCEPSS rescore
  3. 2026-07-13 06:13 UTCEPSS rescore
  4. 2026-07-13 06:13 UTCEPSS rescore
  5. 2026-07-12 23:49 UTCGHSA enrichment
  6. 2026-07-12 05:46 UTCEPSS rescore
  7. 2026-07-11 23:26 UTCGHSA enrichment
  8. 2026-07-11 08:27 UTCEPSS rescore
  9. 2026-07-11 08:27 UTCEPSS rescore
  10. 2026-07-10 23:03 UTCGHSA enrichment
  11. 2026-07-09 22:40 UTCGHSA enrichment
  12. 2026-07-09 19:10 UTCEPSS rescore
  13. 2026-07-09 19:10 UTCEPSS rescore
  14. 2026-07-08 22:17 UTCGHSA enrichment
  15. 2026-07-08 15:16 UTCEPSS rescore
  16. 2026-07-08 15:16 UTCEPSS rescore
  17. 2026-07-07 21:55 UTCGHSA enrichment
  18. 2026-07-07 13:46 UTCEPSS rescore
  19. 2026-07-07 13:46 UTCEPSS rescore
  20. 2026-07-06 21:32 UTCGHSA enrichment
  21. 2026-07-06 16:27 UTCEPSS rescore
  22. 2026-07-06 16:27 UTCEPSS rescore
  23. 2026-07-06 02:23 UTCEPSS rescore
  24. 2026-07-06 02:23 UTCEPSS rescore
  25. 2026-07-05 21:10 UTCGHSA enrichment
  26. 2026-07-05 02:31 UTCEPSS rescore
  27. 2026-07-05 02:30 UTCEPSS rescore
  28. 2026-07-04 20:45 UTCGHSA enrichment
  29. 2026-07-04 06:31 UTCEPSS rescore
  30. 2026-07-04 06:31 UTCEPSS rescore
  31. 2026-07-03 20:22 UTCGHSA enrichment
  32. 2026-07-02 19:59 UTCGHSA enrichment
  33. 2026-07-01 19:37 UTCGHSA enrichment
  34. 2026-07-01 15:07 UTCEPSS rescore
  35. 2026-06-30 23:22 UTCEPSS rescore
  36. 2026-06-30 19:15 UTCGHSA enrichment
  37. 2026-06-29 18:52 UTCGHSA enrichment
  38. 2026-06-29 14:06 UTCEPSS rescore
  39. 2026-06-29 14:06 UTCEPSS rescore
  40. 2026-06-28 18:29 UTCGHSA enrichment
  41. 2026-06-28 14:07 UTCEPSS rescore
  42. 2026-06-28 04:56 UTCEPSS rescore
  43. 2026-06-28 04:56 UTCEPSS rescore
  44. 2026-06-27 18:06 UTCGHSA enrichment
  45. 2026-06-27 03:08 UTCEPSS rescore
  46. 2026-06-26 17:44 UTCGHSA enrichment
  47. 2026-06-25 17:21 UTCGHSA enrichment
  48. 2026-06-25 13:49 UTCEPSS rescore
  49. 2026-06-24 16:59 UTCGHSA enrichment
  50. 2026-06-24 14:05 UTCEPSS rescore
  51. 2026-06-23 21:33 UTCEPSS rescore
  52. 2026-06-23 21:33 UTCEPSS rescore
  53. 2026-06-23 16:36 UTCGHSA enrichment
  54. 2026-06-22 19:39 UTCNVD updateCVSS v4 → 6.9
  55. 2026-06-22 16:13 UTCGHSA enrichment
  56. 2026-06-21 15:38 UTCEG score recompute
  57. 2026-06-21 15:38 UTCGHSA enrichment

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-56299?
CVE-2026-56299 is a medium vulnerability published on June 21, 2026. Capgo before 12.128.2 contains an authentication bypass vulnerability in the /build/upload/:jobId/* endpoint that allows unauthenticated attackers to trigger consistent 500 errors. Remote attackers can send OPTIONS requests to bypass authentication middleware and invoke tusProxy logic with invalid…
When was CVE-2026-56299 disclosed?
CVE-2026-56299 was first published in the National Vulnerability Database on June 21, 2026, with the most recent update on June 23, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-56299 actively exploited?
CVE-2026-56299 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1% probability of exploitation in the next 30 days, which ranks it in the top 51.2% of all scored CVEs.
What is the CVSS score of CVE-2026-56299?
CVE-2026-56299 has a CVSS v3 base score of 5.3 (NVD).
How do I remediate CVE-2026-56299?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-56299, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

Explore the affected products and dependency analysis for CVE-2026-56299

Explore →

Is Your Infrastructure Affected by CVE-2026-56299?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs