CVE-2026-63178

MEDIUMPre-NVD 6.56.5—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 6.5 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.3%, top 79% of all CVEs by exploit prediction. 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
Elevated
6.5EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 6.5Exploit: Elevated riskExposed: 0

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

Onyx is an open-source AI platform. Prior to 4.3.0, Onyx Enterprise Edition's PATCH /manage/admin/user-group/{user_group_id} and POST /manage/admin/user-group/{user_group_id}/add-users endpoints in ee/onyx/server/user_group/api.py call update_user_group and add_users_to_user_group in ee/onyx/db/user_group.py without enforcing _validate_curator_can_modify_group, allowing a curator to add accounts to arbitrary groups and obtain document access through get_acl_for_user and the OpenSearch access_control_list filter. This issue is fixed in version 4.3.0.

CVSS v3
6.5
EG Score
6.5(medium)
EG Risk
45(Track*)
EG Risk 45/100SSVC: 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
Severity65% × 45%
Exploitation40% × 40%
Automatability0% × 15%
Action: Watch closely — could escalate to Attend.
EPSS PROB
0%
EPSS %ILE
21%
KEV
Not listed

Published

August 17, 2026

Last Modified

August 18, 2026

Advisory Details (6)

Auto-updated Aug 17, 2026
🔬 Proof of concept available. Patch available. Sources: github_commit, github_release, github, github_pr.
github_release Patch Available

v4.3.0

Patch available: onyx-dot-app/onyx v4.3.0

https://github.com/onyx-dot-app/onyx/releases/tag/v4.3.0
github_commit

commit b9e1c6894be3 (onyx-dot-app/onyx)

Fix landed in onyx-dot-app/onyx commit b9e1c6894be3 — awaiting tagged release

https://github.com/onyx-dot-app/onyx/commit/b9e1c6894be3c237283f4b5fd4eb0af935b40664
github_commit

commit 46e19cc2750f (onyx-dot-app/onyx)

Fix landed in onyx-dot-app/onyx commit 46e19cc2750f — awaiting tagged release

https://github.com/onyx-dot-app/onyx/commit/46e19cc2750fed659488cb12a1f171016ba5a099
github_pr

fix(ee): scope curator group writes to curated groups (#12525) to release v4.3

Fix merged in onyx-dot-app/onyx PR #12549 on 2026-06-30 — awaiting tagged release

https://github.com/onyx-dot-app/onyx/pull/12549
github_pr

fix(ee): scope curator group writes to curated groups

Fix merged in onyx-dot-app/onyx PR #12525 on 2026-06-30 — awaiting tagged release

https://github.com/onyx-dot-app/onyx/pull/12525
github Patch Available🟡 PoC Available

Curator-scope IDOR: any curator can modify membership of arbitrary user groups via unscoped PATCH /manage/admin/user-group/{id} and /add-users leading to cross-group document disclosure · Advisory · onyx-dot-app/onyx · GitHub

https://github.com/onyx-dot-app/onyx/security/advisories/GHSA-7f48-vgpj-h95m

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 9× in last 7d / 18× 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. 2026-08-27 09:13 UTCEG score recompute
  2. 2026-08-26 14:46 UTCEPSS rescore
  3. 2026-08-26 07:08 UTCEG score recompute
  4. 2026-08-25 13:49 UTCEPSS rescore
  5. 2026-08-25 05:02 UTCEG score recompute
  6. 2026-08-23 00:55 UTCEG score recompute
  7. 2026-08-23 00:19 UTCEPSS rescore
  8. 2026-08-21 23:49 UTCEPSS rescore
  9. 2026-08-21 22:52 UTCEG score recompute
  10. 2026-08-20 22:55 UTCEPSS rescore
  11. 2026-08-19 18:46 UTCEG score recompute
  12. 2026-08-19 17:04 UTCEPSS rescore
  13. 2026-08-18 16:43 UTCEG score recompute
  14. 2026-08-18 16:00 UTCEG score recompute
  15. 2026-08-18 13:48 UTCEPSS rescore
  16. 2026-08-17 22:21 UTCEG score recompute
  17. 2026-08-17 21:40 UTCEG score recompute
  18. 2026-08-17 21:39 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-63178?
CVE-2026-63178 is a medium vulnerability published on August 17, 2026. Onyx is an open-source AI platform. Prior to 4.3.0, Onyx Enterprise Edition's PATCH /manage/admin/user-group/{usergroupid} and POST /manage/admin/user-group/{usergroupid}/add-users endpoints in ee/onyx/server/usergroup/api.py call updateusergroup and adduserstousergroup in ee/onyx/db/usergroup.py…
When was CVE-2026-63178 disclosed?
CVE-2026-63178 was first published in the National Vulnerability Database on August 17, 2026, with the most recent update on August 18, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-63178 actively exploited?
CVE-2026-63178 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 79.5% of all scored CVEs.
What is the CVSS score of CVE-2026-63178?
CVE-2026-63178 has a CVSS v3 base score of 6.5 (NVD).
How do I remediate CVE-2026-63178?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-63178, 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-2026-63178

Explore →

Is Your Infrastructure Affected by CVE-2026-63178?

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

Start Free Scan →Browse All CVEs