What is CVE-2026-56708?

CVE-2026-56708 is a medium-severity vulnerability in Getgrav Grav, classified under Time-of-check Time-of-use (TOCTOU) Race Condition. CVSS score: 5.3/10. Published 2026-08-25.

How severe is CVE-2026-56708?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Vulnerability in Getgrav Grav

CVE-2026-56708

Grav API plugin before 1.0.16 contains a server-side request forgery vulnerability in webhook delivery that allows attackers to bypass hostname validation by DNS rebinding. Attackers controlling authoritative DNS for a configured webhook hostname can answer validation lookups with public addresses and delivery lookups with private addresses to reach internal network resources.

Vulnerability class: TOCTOU (Time-of-Check to Time-of-Use)

Published 2026-08-25 · last modified 2026-08-31.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N.

EPSS exploit prediction

EPSS: 0.003 (19.0th percentile), scored 2026-10-10.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 19th percentile — 19.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.001

Affected products

Getgrav Grav

Weakness classification (CWE)

CWE-367 — Time-of-check Time-of-use (TOCTOU) Race Condition

References

github.com/getgrav/grav/security/advisories/GHSA-hq2v-cgw4-fw2w (vendor-advisory)
www.vulncheck.com/advisories/grav-api-plugin-before-ssrf-via-dns-rebinding (third-party-advisory)

Frequently asked questions

What is CVE-2026-56708?: CVE-2026-56708 is a medium-severity vulnerability in Getgrav Grav, classified under Time-of-check Time-of-use (TOCTOU) Race Condition. CVSS score: 5.3/10. Published 2026-08-25.
How severe is CVE-2026-56708?: Medium severity. CVSS v3 base score is 5.3 out of 10.