Cacti: Authenticated RCE on Data Input

published 2026-10-23 16 d ago modified 2026-10-29 10 d ago also EUVD-2026-109088

cvss: 7.2; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.4%; EPSS 0.4% chance of exploitation in 30 days, percentile 34%
public exploits: 0; none known

Cacti is an open source performance and fault management framework. Prior to version 1.2.31, the prior blocklist ([;&| `$\\n\r]) omitted single-quote, double-quote, redirect operators, subshell parens and braces. An authenticated admin could save an input_string` containing single-quote, redirect operator, or subshell parens, and pass the check. This issue has been patched in version 1.2.31.

Patch / fix

fixed in 1 distros 1 links 1

cacti cacti 1.2.31

cacti Debian 14 1.2.31+ds1-1

debian advisories DEBIAN-CVE-2026-39902

github.com/Cacti/cacti#7112 pull request

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-39902 updated 2026-11-02 cvss 7.2

cacti: Cacti: Arbitrary command execution via incomplete character blocklist

Red Hat All currently supported Red Hat products
not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: total
Assessed: 11 d ago (2026-10-29)

Exploit prediction

0.40% chance of exploitation in the next 30 days, higher than 34% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	7.2	CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

Affected products

Cacti cacti

Classification

Weakness

CWE-78 Improper Neutralization of Special Elements used in an OS Command

References

Sources

CVE List CVE-2026-39902
NVD CVE-2026-39902

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.

Summary