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Jul 28, 2026

2 min

Sploitus

  • nginx
  • f5
  • cve
  • http2
  • grpc
  • heap-overflow
  • reverse-proxy

news

NGINX 2026 Data-Plane Multi-CVE Pack (Proxy/Rewrite/Map/OCSP)

CTI pack covering five config-dependent NGINX data-plane CVEs (OCSP bypass, HTTP/2 injection, rewrite/map/gRPC heap overflows); public scanners indexed on Sploitus.

Summary

A July 2026 Sploitus-indexed NGINX multi-CVE investigation pack (author Pratik Chhetri, report date 2026-07-28) aggregates five configuration-dependent data-plane issues affecting NGINX Open Source / Plus. They are distinct from the earlier NGINX Rift rewrite-module line (CVE-2026-42945), though they share the same “internet-facing reverse proxy / Ingress” risk surface.

Public GitHub activity and at least one scanner were noted for several IDs; CISA KEV listings were not found for these five at report time. OFFSITE.DARK indexes the Sploitus CTI card for defenders prioritizing patch + config audit.

CVE pack

CVEComponentIssueFixed OSS (approx.)Priority (pack)
CVE-2026-28755ngx_stream_ssl_moduleOCSP result bypass in stream mTLS1.29.7+ / 1.28.3+P3/P2
CVE-2026-42926ngx_http_proxy_v2_moduleHTTP/2 upstream request injection1.31.0+ / 1.30.1+P2
CVE-2026-9256ngx_http_rewrite_moduleHeap overflow via overlapping PCRE captures1.31.1+ / 1.30.2+P1
CVE-2026-42055proxy_v2 + gRPC modulesHeap overflow with large HTTP/2/gRPC headers1.31.2+ / 1.30.3+P1
CVE-2026-42533map + regexHeap overflow via regex map capture clobbering1.31.3+ / 1.30.4+P0/P1

Highest EPSS called out in the pack: CVE-2026-9256 (~0.099).

Risk surface

Exposure rises when configs include:

  • Internet-facing reverse proxies / API gateways / Ingress Controllers
  • proxy_http_version 2 + body/header rewriting
  • gRPC gateways with large headers
  • Regex-heavy rewrite / map capture usage
  • Stream mTLS with OCSP stapling/validation paths

Impact

Worker crash or potential code execution on heap-overflow CVEs; unauthorized acceptance of revoked certs on the OCSP bypass; upstream frame injection on HTTP/2 proxy paths. Impact is config-gated — inventory matters as much as version number.

Mitigation

  1. Upgrade NGINX Open Source / Plus (and Ingress Controller images) to the fixed trains above.
  2. Audit for HTTP/2 upstream, gRPC, stream mTLS+OCSP, and overlapping regex capture patterns.
  3. Prefer vendor-supported Plus/OSS packages over stale static builds in containers.
  4. Cross-check NGINX Rift if still on rewrite/set capture patterns from the May 2026 wave.
  5. Monitor for public scanners targeting CVE-2026-42533 and related PoCs.

Sources

→ Source