CVE-2026-56434

MEDIUMPre-NVD 6.56.5—
EchelonGraph scoreHIGH confidence

Score 6.5 from GitHub Security Advisory (severity: HIGH) published 2026-07-15. a secondary CVSS source baseline 6.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: ghsa, secondary
Trending — 4 sources updated this week
6.5
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS: 0%CVSS: 6.5Exploit: NoneExposed: 0

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

NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_ssi_module module. This vulnerability may exist when the Server-Side Includes (SSI), proxy_pass, and proxy_buffering off directives are configured. With this configuration, an unauthenticated attacker with man-in-the-middle (MITM) ability to control responses from an upstream server may be able to cause a use-after-free in the NGINX worker process. This issue may lead to limited modification of memory or a restart of the NGINX worker process.

Impact: This vulnerability may allow remote attackers to have limited control to modify memory contents or restart the NGINX worker process. There is no control plane exposure; this is a data plane issue only.

Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

CVSS v3
6.5
EG Score
6.5(high)
EPSS
31.0%
KEV
Not listed

Published

July 15, 2026

Last Modified

July 15, 2026

Advisory Details (1)

Auto-updated Jul 15, 2026
No patch confirmed yet.
generic

myF5

https://my.f5.com/manage/s/article/K000162098

Vendor Advisories for CVE-2026-56434(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 5× in last 7d / 5× 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. 2026-07-16 17:03 UTCEPSS rescore
  2. 2026-07-16 15:10 UTCEG score recompute
  3. 2026-07-16 15:10 UTCGHSA enrichment
  4. 2026-07-15 14:50 UTCEG score recompute
  5. 2026-07-15 14:49 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-56434?
CVE-2026-56434 is a medium vulnerability published on July 15, 2026. NGINX Plus and NGINX Open Source have a vulnerability in the ngxhttpssimodule module. This vulnerability may exist when the Server-Side Includes (SSI), proxypass, and proxy_buffering off directives are configured. With this configuration, an unauthenticated attacker with man-in-the-middle (MITM)…
When was CVE-2026-56434 disclosed?
CVE-2026-56434 was first published in the National Vulnerability Database on July 15, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-56434 actively exploited?
CVE-2026-56434 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 31.0% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-56434?
CVE-2026-56434 has a CVSS v3 base score of 6.5 (NVD).
How do I remediate CVE-2026-56434?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-56434, 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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