CVE-2026-78851

Status: DeferredMedium (6.5)—PoC

Severity6.5Medium · CVSS 3.1

Exploitation probability1.12 %higher than 66% of CVEs

Active exploitationNonot in the CISA catalog

Public exploitAvailableProof of concept on GitHub (unverified)

Directory Traversal vulnerability in Grav CMS 2.0.3 through 2.0.6 allows a remote attacker to obtain sensitive information via the GravExtension.php and the mediaDirFunc method.

CVSS

Base score: 6.5
Version: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 1.12 %
Percentile among all scored CVEs: 66
Score date: 10/20/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

Public exploits

Exploit code or detection templates are publicly available. This is not the same as confirmed active exploitation (KEV), but it raises the risk: patch with priority.

Proof of concept on GitHub (unverified) · List of proofs of concept on GitHub

⚠️ GitHub proofs of concept are not verified: some are fake or contain malware. Never run them outside an isolated lab.

ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

ExploitationT1210 Exploitation of Remote Serviceslateral movement90 %
Primary impactT1005 Data from Local Systemcollection75 %

El vector CVSS AV:N/PR:L indica red con privilegios bajos, lo que da T1210; la descripción indica que el atacante obtiene información sensible mediante directory traversal (CWE-22/CWE-200).

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

ATT&CK mitigations that cover these techniques

Vulnerability Scanning Threat Intelligence Program Privileged Account Management Network Segmentation Disable or Remove Feature or Program Application Isolation and Sandboxing

Affected technologies (1)

⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.

Getgrav — Grav^AI

CWEs

CWE-22, CWE-200

References

Show 5 references

Raw JSON (NVD)

Show

{
  "id": "CVE-2026-78851",
  "cveTags": [],
  "metrics": {
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        "ssvcData": {
          "id": "CVE-2026-78851",
          "role": "CISA Coordinator",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "version": "2.0.3",
          "timestamp": "2026-10-15T18:46:12.816122Z"
        }
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    ],
    "cvssMetricV31": [
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          "baseScore": 6.5,
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          "baseSeverity": "MEDIUM",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
          "integrityImpact": "NONE",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "NONE",
          "privilegesRequired": "LOW",
          "confidentialityImpact": "HIGH"
        },
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        "exploitabilityScore": 2.8
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  "affected": [
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      "affectedData": [
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  "published": "2026-10-15T17:17:28.640",
  "references": [
    {
      "url": "https://github.com/SLO-CYBER-SEC/CVE-2026-78851",
      "source": "cve@mitre.org"
    },
    {
      "url": "https://github.com/getgrav/grav",
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    {
      "url": "https://github.com/getgrav/grav/blob/2.0.6/system/config/security.yaml#L325",
      "source": "cve@mitre.org"
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      "description": [
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  "descriptions": [
    {
      "lang": "en",
      "value": "Directory Traversal vulnerability in Grav CMS 2.0.3 through 2.0.6 allows a remote attacker to obtain sensitive information via the GravExtension.php and the mediaDirFunc method."
    }
  ],
  "lastModified": "2026-10-16T19:56:15.773",
  "sourceIdentifier": "cve@mitre.org"
}