SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2026-23929

Prototype pollution vulnerability in searchParamsToObject() is leading to a persistent XSS in Maps.

HIGH 8.5EPSS 0.26%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.26%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

Prototype pollution vulnerability in searchParamsToObject() is leading to a persistent XSS in Maps. URL parameter processing was not filtering dangerous properties like __proto__, combined with jQuery's unsafe element creation that traversed the prototype chain.

CVSS 4.0
8.5 HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS
0.26% probability · 17th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-1321
Affected
zabbix/zabbix
Source
security@zabbix.com
EPSS trend
0%3%5%26 October 2026: 0.26%26 October 202626 October 2026

EPSS 0.3% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.