Grav before 9.1.8 contains an arbitrary file write vulnerability in the Form plugin's process.save.filename parameter, which is validated against path traversal before Twig processing but never re-validated after rendering. Attackers can submit form data containing path traversal sequences that are processed through Twig templates, allowing them to write arbitrary files including PHP webshells to the web root or other sensitive directories.
CVE-2026-61873
HIGHPre-NVD 8.18.1—Trending — 3 sources updated this weekElevated
EchelonGraph scoreHIGH confidence
Score 8.1 from GitHub Security Advisory (severity: HIGH) published 2026-07-15. a secondary CVSS source baseline 8.1; sources differ by 0.0.
Triggered by: GitHub Security Advisory CVSS
Sources: ghsa, secondary
8.1
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
- High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: —CVSS: 8.1Exploit: NoneExposed: 0
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 8.1
- EG Score
- 8.1(high)
- EPSS
- —
- KEV
- Not listed
Published
July 15, 2026
Last Modified
July 15, 2026
Advisory Details (2)
Auto-updated Jul 15, 2026🔬 Proof of concept available. Patch available. Sources: github.
generic
Grav before 9.1.8 Arbitrary File Write via Twig-Processed Filename | Advisories | VulnCheck
https://www.vulncheck.com/advisories/grav-before-arbitrary-file-write-via-twig-processed-filenamegithub Patch Available🟡 PoC Available
Arbitrary File Write via Twig-Processed Filename -TOCTOU in Form `process.save.filename` · Advisory · getgrav/grav · GitHub
https://github.com/getgrav/grav/security/advisories/GHSA-q532-mvx7-42qgVendor Advisories for CVE-2026-61873(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 4× in last 7d / 4× 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.
- 2026-07-16 00:39 UTCEG score recompute
- 2026-07-16 00:39 UTCGHSA enrichment
- 2026-07-15 11:54 UTCEG score recompute
- 2026-07-15 11:54 UTCMITRE cvelistV5first tracked
Frequently asked(4)
What is CVE-2026-61873?
CVE-2026-61873 is a high vulnerability published on July 15, 2026. Grav before 9.1.8 contains an arbitrary file write vulnerability in the Form plugin's process.save.filename parameter, which is validated against path traversal before Twig processing but never re-validated after rendering. Attackers can submit form data containing path traversal sequences that are…
When was CVE-2026-61873 disclosed?
CVE-2026-61873 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.
What is the CVSS score of CVE-2026-61873?
CVE-2026-61873 has a CVSS v3 base score of 8.1 (NVD).
How do I remediate CVE-2026-61873?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-61873, 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-2026-61873
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