CVE-2026-63177

HIGHPre-NVD 7.17.1—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 7.1 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.2%, top 91% 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
7.1EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 7.1Exploit: None knownExposed: 0

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

Malcolm is a network traffic analysis tool suite. Prior to version 26.07.0, role-based access control enforced in the Nginx OpenResty Lua layer evaluates the raw, unnormalized ngx.var.request_uri, while Nginx itself routes requests using the normalized path. An authenticated low-privilege user can prepend a traversal segment (for example /x/../upload/...) so that Nginx routes the request to a restricted backend while the Lua role check fails to match any rule and falls open, granting access it should deny. Version 26.07.0 fixes the issue.

CVSS v3
7.1
EG Score
7.1(medium)
EG Risk
32(Track)
EG Risk 32/100SSVC: 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
Severity71% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
9%
KEV
Not listed

Published

August 11, 2026

Last Modified

August 12, 2026

Advisory Details (1)

Auto-updated Aug 11, 2026
🔬 Proof of concept available. Patch available. Sources: github.
github Patch Available🟡 PoC Available

Authorization Bypass via URI Normalization Differential in Nginx Lua RBAC · Advisory · cisagov/Malcolm · GitHub

https://github.com/cisagov/Malcolm/security/advisories/GHSA-m5fr-rv3h-xg2r

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 10× in last 7d / 36× 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. 2026-08-30 01:22 UTCEPSS rescore
  2. 2026-08-29 08:59 UTCEG score recompute
  3. 2026-08-28 21:42 UTCEPSS rescore
  4. 2026-08-28 00:52 UTCEG score recompute
  5. 2026-08-27 14:25 UTCEPSS rescore
  6. 2026-08-27 01:20 UTCEG score recompute
  7. 2026-08-26 14:46 UTCEPSS rescore
  8. 2026-08-25 14:24 UTCEG score recompute
  9. 2026-08-25 13:49 UTCEPSS rescore
  10. 2026-08-24 15:06 UTCEG score recompute
  11. 2026-08-23 04:10 UTCEG score recompute
  12. 2026-08-23 00:19 UTCEPSS rescore
  13. 2026-08-22 04:52 UTCEG score recompute
  14. 2026-08-21 23:49 UTCEPSS rescore
  15. 2026-08-21 05:35 UTCEG score recompute
  16. 2026-08-20 22:55 UTCEPSS rescore
  17. 2026-08-19 18:40 UTCEG score recompute
  18. 2026-08-19 17:04 UTCEPSS rescore
  19. 2026-08-18 19:07 UTCEG score recompute
  20. 2026-08-18 13:48 UTCEPSS rescore
  21. 2026-08-17 19:47 UTCEG score recompute
  22. 2026-08-17 13:47 UTCEPSS rescore
  23. 2026-08-16 20:30 UTCEG score recompute
  24. 2026-08-16 14:56 UTCEPSS rescore
  25. 2026-08-16 08:51 UTCEG score recompute
Show 11 more
  1. 2026-08-15 09:34 UTCEG score recompute
  2. 2026-08-15 01:30 UTCEPSS rescore
  3. 2026-08-13 22:38 UTCEG score recompute
  4. 2026-08-13 22:00 UTCEPSS rescore
  5. 2026-08-12 23:22 UTCEG score recompute
  6. 2026-08-12 22:21 UTCEG score recompute
  7. 2026-08-12 20:35 UTCEG score recompute
  8. 2026-08-12 13:51 UTCEPSS rescore
  9. 2026-08-11 21:18 UTCEG score recompute
  10. 2026-08-11 20:45 UTCEG score recompute
  11. 2026-08-11 20:45 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-63177?
CVE-2026-63177 is a high vulnerability published on August 11, 2026. Malcolm is a network traffic analysis tool suite. Prior to version 26.07.0, role-based access control enforced in the Nginx OpenResty Lua layer evaluates the raw, unnormalized ngx.var.request_uri, while Nginx itself routes requests using the normalized path. An authenticated low-privilege user can…
When was CVE-2026-63177 disclosed?
CVE-2026-63177 was first published in the National Vulnerability Database on August 11, 2026, with the most recent update on August 12, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-63177 actively exploited?
CVE-2026-63177 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 91.5% of all scored CVEs.
What is the CVSS score of CVE-2026-63177?
CVE-2026-63177 has a CVSS v3 base score of 7.1 (NVD).
How do I remediate CVE-2026-63177?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-63177, 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

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