SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAwaiting Analysis

CVE-2026-21391

An improper validation vulnerability exists within PingAM where a well-crafted request allows arbitrary or protected ID Token claims to be set or overridden.

CRITICAL 9.5EPSS 0.45%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.45%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

An improper validation vulnerability exists within PingAM where a well-crafted request allows arbitrary or protected ID Token claims to be set or overridden. In certain configurations this could allow an attacker to bypass authentication controls via spoofing leading to privilege escalation or impersonation.

CVSS 4.0
9.5 CRITICALCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:L/SC:H/SI:H/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS
0.45% probability · 38th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-290
Source
responsible-disclosure@pingidentity.com
EPSS trend
0%3%5%19 September 2026: 0.45%19 September 202619 September 2026

EPSS 0.4% since 19 September 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.