Grav before 3.9.2 fails to validate untrusted Host headers in the sendInvitationEmail() function when constructing token-bearing invitation links. Attackers can manipulate the Host header to poison invitation links and redirect users to attacker-controlled domains, bypassing the require_trusted_host protection which only covers password reset flows.
CVE-2026-56709
HIGHPre-NVD 7.57.5—Trending — 4 sources updated this week
EchelonGraph scoreHIGH confidence
Score 7.5 from GitHub Security Advisory (severity: HIGH) published 2026-08-25. a secondary CVSS source baseline 7.5; sources differ by 0.0.
Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
7.5EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
- High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 7.5Exploit: None knownExposed: 0
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 7.5
- EG Score
- 7.5(high)
- EG Risk
- 38(Track)EG Risk 38/100SSVC: 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 computedSeverity75% × 45%Exploitation0% × 40%Automatability30% × 15%Action: Routine — remediate on your standard cadence. - EPSS PROB
- 0%
- EPSS %ILE
- 17%
- KEV
- Not listed
Published
August 25, 2026
Last Modified
August 25, 2026
Advisory Details (2)
Auto-updated Aug 25, 2026🔬 Proof of concept available. Patch available. Sources: github.
generic
Grav before 3.9.2 Host Header Injection via sendInvitationEmail | Advisories | VulnCheck
https://www.vulncheck.com/advisories/grav-before-host-header-injection-via-sendinvitationemailgithub Patch Available🟡 PoC Available
sendInvitationEmail() is missing the untrusted-Host-header protection the other three security-sensitive email links have, and require_trusted_host only enforces one of four flows · Advisory · getgrav/grav · GitHub
https://github.com/getgrav/grav/security/advisories/GHSA-69vf-mjxw-x79jVendor Advisories for CVE-2026-56709(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 8× in last 7d / 8× 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.
- 2026-08-26 00:54 UTCEG score recompute
- 2026-08-26 00:54 UTCGHSA enrichment
- 2026-08-25 13:49 UTCEPSS rescore
- 2026-08-25 13:37 UTCEG score recompute
- 2026-08-25 13:37 UTCGHSA enrichment
- 2026-08-25 02:19 UTCEG score recompute
- 2026-08-25 01:50 UTCEG score recompute
- 2026-08-25 01:50 UTCMITRE cvelistV5first tracked
Frequently asked(5)
What is CVE-2026-56709?
CVE-2026-56709 is a high vulnerability published on August 25, 2026. Grav before 3.9.2 fails to validate untrusted Host headers in the sendInvitationEmail() function when constructing token-bearing invitation links. Attackers can manipulate the Host header to poison invitation links and redirect users to attacker-controlled domains, bypassing the requiretrustedhost…
When was CVE-2026-56709 disclosed?
CVE-2026-56709 was first published in the National Vulnerability Database on August 25, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-56709 actively exploited?
CVE-2026-56709 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 83.1% of all scored CVEs.
What is the CVSS score of CVE-2026-56709?
CVE-2026-56709 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2026-56709?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-56709, 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-2026-56709
Is Your Infrastructure Affected by CVE-2026-56709?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.