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.

CVSS v3 2.9 LOW

2.9^/10

CVSS v3 : LOW

Vector :

Exploitability : 1.4 / Impact : 1.4

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/Cacti/cacti/commit/d2a698854956e9e4e53da9eab5b5719ae40e6893	Patch
https://github.com/Cacti/cacti/issues/7011	Issue Tracking Patch
https://github.com/Cacti/cacti/security/advisories/GHSA-23g4-vf2j-94w4	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:cacti:cacti:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-06-24 22:16

Updated : 2026-06-25 20:19

NVD link : CVE-2026-39894

Mitre link : CVE-2026-39894

CVE.ORG link : CVE-2026-39894

JSON object : View

Products Affected

cacti

cacti

CWE

CWE-474

Use of Function with Inconsistent Implementations

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