CVE-2026-39893

Cacti: Pre-authentication SQL injection via rfilter RLIKE clause in graph_view.php

No known exploitation. EPSS puts it in the 50th percentile. A vendor fix is available.

CVSS 3.19.8Critical EPSS percentile50th0.7% chance in 30 days CISA KEVNot listedNo confirmed exploitation
No public exploit known FixVendor fixNo build named by the sources

Published 2026-06-24Updated 2026-06-26Sources: CVE.org, NVD

NVD CVE.org

What to do

The vendor has published a fix. Version details are below where the sources state them.

Steps

Written by AI from the record

Check whether your Cacti guest viewing feature is enabled in your Cacti configuration.
Check your Cacti version number and whether it is 1.2.30 or earlier.
Upgrade Cacti to version 1.2.31 or later (this is the fixed version).

Vendor advisory Usually a quick update

Check it yourselfA free OpenVAS check exists for this CVE. Run it against your hosts.Is your organisation exposed?Request an assessment to establish which checks fit your systems.

What it is

From the CVE record

Cacti is an open source performance and fault management framework. In versions 1.2.30 and prior, the rfilter request variable was concatenated into a RLIKE SQL clause without sanitization. The endpoint does not require authentication (graph viewing supports guest access via the configured guest user), so the SQLi was reachable pre-auth on installs with guest viewing enabled. This issue was fixed in version 1.2.31.

In plain language

Written by AI from the record

Cacti versions 1.2.30 and earlier have an unauthenticated SQL injection flaw in the graph viewing page; if your Cacti “guest viewing” is enabled, a typical small business should treat this as a serious fix-now issue.

Unauthenticated SQL injection in Cacti’s `graph_view.php` via the `rfilter` parameter’s `RLIKE` clause allows arbitrary database read/modify/delete when guest viewing is enabled.

If you're affected

Database content theft
Database content tampering
Service disruption
Possible data corruption

What is it

This vulnerability lets someone “break into” Cacti’s database using a trick in a URL parameter for viewing graphs. If guest viewing is turned on, the attacker doesn’t need an account—so they may be able to read, change, or delete data that Cacti uses. Think of it like leaving a spare key under the mat and then finding a way to use that key to unlock the office computer and alter its files.

Who is affected

This matters if you run the open-source monitoring/app called Cacti and expose its graph viewing to unauthenticated (guest) users. The risk specifically requires that guest viewing is enabled in Cacti’s configuration; otherwise the pre-auth path may not be reachable. It’s most relevant for systems reachable over the network where guest access can be used.

How urgent is it

This is an AMBER issue because it is pre-authentication: an attacker can reach the vulnerable feature without logging in if guest viewing is enabled. While there’s no KEV listing and no public exploit code noted, the impact includes the ability to read or modify database contents, so you should upgrade promptly.

What to do — in detail

Confirm exposure (configuration check): In Cacti, verify whether guest viewing is enabled (the vulnerability depends on guest viewing being turned on). If guest viewing is disabled, you may not be reachable pre-auth through this path.
Confirm software version: Identify the exact Cacti version in use. The flaw affects Cacti 1.2.30 and earlier.
Upgrade to the fix: Upgrade Cacti to 1.2.31 or later.
- Fixed version: 1.2.31.
- Patch references: https://github.com/Cacti/cacti/pull/7039 and the corresponding advisory (GHSA-69gg-mjfm-jjpc).
If you cannot upgrade immediately (mitigation while waiting): Disable guest viewing in the Cacti configuration so that the vulnerable graph-viewing endpoint is not accessible without authentication.
After upgrading:
- Re-check guest viewing is still configured intentionally for your business needs.
- Review web server access logs for unusual requests to graph_view.php containing suspicious rfilter patterns.
- Monitor Cacti logs for database errors or abnormal activity around graph viewing.
Due dates / KEV: This CVE is not listed in CISA KEV, so no CISA-specific due date is provided in the findings.

Technical context

Severity is high/critical in practical terms because the vulnerability is pre-auth (no login required) and can impact the database (read/modify/delete). Mechanism: SQL injection in Cacti’s graph_view.php where the rfilter request variable is concatenated into a RLIKE SQL clause without sanitization. Attack vector is network-based access to the graph viewing functionality. Exploitation status: not listed in CISA KEV; no public exploit code recorded in the findings. A fix is available in Cacti 1.2.31 (per the patch cards). Attack precondition: guest viewing must be enabled in Cacti’s configuration for the pre-auth reachability described in the findings.

This is a general assessment based on public vulnerability data. It does not account for your specific infrastructure — when in doubt, consult a security specialist.

Exploitation

Where each signal puts this CVE on the scale from published to confirmed exploited.

EPSS50th

CISA KEV

Not in the catalog. CISA has not confirmed exploitation.

Public exploits

No public exploit or proof of concept found in the sources we track.

EPSS

0.7% chance of exploitation activity in the next 30 days, which ranks it in the 50th percentile of scored CVEs.

Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.

Lifecycle

6 events over 2 days, from the signal feeds we watch.

2026-06-26Patch availablerecord updated
2026-06-25OpenVAS check added
2026-06-24Publishedweakness classified, att&ck mapped

Affected products

Cactioss-project
- cactiWeb AppOn-premEnterprise Software / itsm-monitoring

And 1 more affected product. See all after sign-in

Technical detail

CVSS 3.1 vector

Open in the CVSS calculator

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Scored 9.8 by NVD.

How it is reached

Attack Vector NetworkExploitable remotely over the network without any special conditions
Attack Complexity LowNo special conditions — the attack can be reliably reproduced
Privileges Required NoneNo authentication required — anyone can exploit this
User Interaction NoneNo user interaction needed — fully automated exploitation

Scope

Scope UnchangedImpact is limited to the vulnerable component itself

Impact if exploited

Confidentiality HighTotal information disclosure — all data in the component is compromised
Integrity HighTotal loss of integrity — attacker can modify any data in the component
Availability HighTotal denial of service — the component is completely unavailable