Reference page — cumulative record through Saturday, October 3, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.
CVE-2026-63177
cisagov Malcolm — Malcolm Vulnerable to Authorization Bypass via URI Normalization Differential in Nginx Lua RBAC
AV AC AT PR UI VC VI VA CVSS EPSS %ile KEV
N L N L N H L N 7.1 .0030 20.7 —
AFFECTED
Product Versions Fixed
Malcolm < 26.07.0 – 26.07.0
TIMELINE
Jul 15 Reserved by GitHub_M
Aug 11 Published (CNA: GitHub_M)
Oct 2 PATCH SHIPPED — CVE-2026-63177 (cisagov Malcolm). Fixed in Malcolm 26.07.0.
Description
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.
Lifecycle
Complete event history — 3 events, chronological
| Date | Event | Detail |
|---|
| July 15, 2026 | Reserved | Reserved by GitHub_M |
| August 11, 2026 | Published | Published (CNA: GitHub_M) |
| October 2, 2026 | PATCH SHIPPED | PATCH SHIPPED — CVE-2026-63177 (cisagov Malcolm). Fixed in Malcolm 26.07.0. |
Affected
Affected products and packages — 1 row
| Vendor | Product / Package | Ecosystem | Version introduced | Fixed |
|---|
| cisagov | Malcolm | — | < 26.07.0 | 26.07.0 |
About this page
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-63177 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Saturday, October 3, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.
