CVE-2025-12739 | Cross-Site Scripting (XSS) in Looker's Extension Loader leading to Admin Account Compromise

An attacker with viewer permissions in Looker could craft a malicious URL that, when opened by a Looker admin, would execute an attacker-supplied script. Exploitation required at least one Looker extension installed on the instance. Looker-hosted and Self-hosted were found to be vulnerable. This issue has already been mitigated for Looker-hosted instances. No user action is required for these. Self-hosted instances must be upgraded as soon as possible. This vulnerability has been patched in all supported versions of Self-hosted. The versions below have all been updated to protect from this vulnerability. You can download these versions at the Looker download page https://download.looker.com/ : * 24.18.201+ * 25.0.79+ * 25.6.66+ * 25.12.7+ * 25.16.0+ * 25.18.0+ * 25.20.0+

Published: 2025-11-24 Last update: 2026-04-15 Assigner: f45cbf4e-4146-4068-b7e1-655ffc2c548c Source: f45cbf4e-4146-4068-b7e1-655ffc2c548c
NVD Status：Deferred，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2025-12739 is rated Low Risk (34.6/100): CVSS High severity, with low exploitation likelihood (EPSS 0.05%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2025-12739

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-04 0.04% 0.05% +0.01%
2 2026-04-22 0.06% 0.04% -0.01%
3 2026-01-31 — 0.06% —

Full EPSS history (4 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-12739

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.3 4.0 HIGH
CVSS:4.0/AV:N/AC:L/AT:P/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/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Red Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network.
Attack complexity (AC:L)
Exploitation conditions are straightforward and stable.
Attack requirements (AT:P)
Additional preconditions must be present for exploitation.
Privileges required (PR:L)
Low privileges are required.
User interaction (UI:A)
User interaction is required in an active way.
Vulnerable system confidentiality impact (VC:H)
High confidentiality impact on the vulnerable system.
Vulnerable system integrity impact (VI:H)
High integrity impact on the vulnerable system.
Vulnerable system availability impact (VA:H)
High availability impact on the vulnerable system.
Subsequent system confidentiality impact (SC:N)
No confidentiality impact on subsequent systems.
Subsequent system integrity impact (SI:N)
No integrity impact on subsequent systems.
Subsequent system availability impact (SA:N)
No availability impact on subsequent systems.
Exploit maturity (threat) (E:X)
Not defined: no reliable threat intelligence; scoring assumes the worst case (equivalent to Attacked).
Confidentiality requirement (CR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Integrity requirement (IR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Availability requirement (AR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Modified attack vector (MAV:X)
Not defined: scoring uses the Base Attack Vector (AV).
Modified attack complexity (MAC:X)
Not defined: scoring uses the Base Attack Complexity (AC).
Modified attack requirements (MAT:X)
Not defined: scoring uses the Base Attack Requirements (AT).
Modified privileges required (MPR:X)
Not defined: scoring uses the Base Privileges Required (PR).
Modified user interaction (MUI:X)
Not defined: scoring uses the Base User Interaction (UI).
Modified vulnerable system confidentiality impact (MVC:X)
Not defined: scoring uses the Base VC metric.
Modified vulnerable system integrity impact (MVI:X)
Not defined: scoring uses the Base VI metric.
Modified vulnerable system availability impact (MVA:X)
Not defined: scoring uses the Base VA metric.
Modified subsequent system confidentiality impact (MSC:X)
Not defined: scoring uses the Base SC metric.
Modified subsequent system integrity impact (MSI:X)
Not defined: scoring uses the Base SI metric.
Modified subsequent system availability impact (MSA:X)
Not defined: scoring uses the Base SA metric.
Safety (supplemental) (S:X)
Not evaluated.
Automatable (supplemental) (AU:X)
Not evaluated.
Recovery (supplemental) (R:X)
Not evaluated.
Value density (supplemental) (V:X)
Not evaluated.
Vulnerability response effort (supplemental) (RE:X)
Not evaluated.
Provider urgency (supplemental) (U:RED)
Red: provider rates highest urgency.
 — — f45cbf4e-4146-4068-b7e1-655ffc2c548c

Weakness enumeration for CVE-2025-12739

Affected software / configurations for CVE-2025-12739

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2025-12739

cvelogic Threat Intelligence