Vulnerability Report

CVE-2026-39894

Title: Cacti Locale-Dependent Decimal Formatting Data Corruption

Other

Proof Of Concept

No public PoC currently indexed for CVE-2026-39894.

CWE Category CWE-474
Published Date Jun 24, 2026
Modified Date Jun 25, 2026
Exploit Status Not Found
Score 2.9 CVSS v3.1
Exploit Probability (EPSS)
0.15%

Vulnerability Summary

CVE-2026-39894: Cacti is an open source performance and fault management framework. In versions 1.2.30 and below, the locale-dependent decimal formatting in rrdtool_function_update() can corrupt RRDtool metric values. The rrdtool_function_update() function checks metric values with is_numeric() and concatenates them into the RRDtool update command via PHP string interpolation. PHP's string cast of floats is locale-sensitive: if LC_NUMERIC uses comma as decimal separator (e.g., de_DE), a value of 1.5 becomes "1,5". RRDtool expects . as decimal separator, causing metric data to shift into wrong columns or be silently dropped. No setlocale() reset is present in the update path. This causes a data integrity issue, but is not remotely exploitable; it requires server locale misconfiguration. The issue has been fixed in version 1.2.31.

Impacted Vendors

T
the_cacti_group 1
C
cacti 1

Reference Links

https://github.com/Cacti/cacti/commit/d2a698854956e9e4e53da9eab5b5719ae40e6893 https://github.com/Cacti/cacti/issues/7011 https://github.com/Cacti/cacti/security/advisories/GHSA-23g4-vf2j-94w4
CVSS v3.1
Source Entity [email protected]
Severity LOW
2.9
Attack Vector
LOCAL
Complexity
HIGH
Privileges
N/A
Interaction
NONE
Confidentiality
N/A
Integrity
N/A
Availability
N/A
Scope
UNCHANGED
RAW VECTOR CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
CVSS v3.1
Source Entity [email protected]
Severity LOW
2.5
Attack Vector
LOCAL
Complexity
HIGH
Privileges
N/A
Interaction
NONE
Confidentiality
N/A
Integrity
N/A
Availability
N/A
Scope
UNCHANGED
RAW VECTOR CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N

Associated Attack Patterns (CAPEC)

Total: Patterns

CVE-2026-39894 Exploits & PoCs (Proof Of Concept)

No public PoCs found in our database for this CVE.

MODIFIED

Vulnerability data updated via NVD.

MODIFIED

Vulnerability data updated via NVD.

MODIFIED

Vulnerability data updated via NVD.

Attack Vector Matrix

Access Vector LOCAL
Complexity HIGH
Privileges N/A
Interaction NONE
CVSS Vector String CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N

Affected Stack

No specific products linked.