critical Known exploitedREV. 01

CVE-2026-48558SimpleHelp — forged identity token grants technician session

SimpleHelp 5.5.15 and earlier accept an OpenID Connect (OIDC) identity token without checking that the identity provider really signed it, so a remote attacker can forge one and land a fully authenticated technician session.

YOUR NEXT MOVE

Upgrade SimpleHelp past 5.5.15 now and rotate technician sessions and credentials; hunt for unfamiliar technician logins using Horizon3's published indicators.

Read the risk

THE VITAL STATS
CVSS score
9.5/ 10
CVSS v4.0
EPSS probability
64%
Likelihood of exploitation
Attack complexity
Low
Conditions needed to exploit
Known exploited
Yes — CISA KEV
CVE published
2026-06-12
Added to KEV
2026-06-29
Exploit published
Not recorded
Confidence
medium
Kill chain
initial access
MITRE ATT&CK
T1190
Severity
critical

CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/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:X

Attacker needsNetwork reach to a SimpleHelp server configured for OpenID Connect login; no account and no user interaction needed.

Behind the card

5 REFERENCES
Field-level provenanceTRACE THE SOURCES +

Which source supports each field, when it was retrieved, and who extracted it.

FieldsSourceRetrievedExtractorConfidence
cvss, exploitation.attack_complexity, exploitation.exploit_available, references, published_atnvd.nist.gov2026-09-23scrty-crds-pipeline/0.1high
exploitation.known_exploited, exploitation.kev_addedcisa.gov2026-09-23scrty-crds-pipeline/0.1high
epssapi.first.org2026-09-23scrty-crds-pipeline/0.1high
title, summary, severity, remediation, mitre_attack, kill_chain, recommended_action, confidence, tags, exploitation.prerequisitesnvd.nist.gov2026-09-23claude-codehigh

Printing history

THE RECORD
  1. r1Initial base card

First printing. This card has not been reprinted since publication.

crds:cve-2026-48558 · CRDS 0.1 · Issued 2026-09-23