Klue Supply Chain Breach Exposes OAuth Tokens and Salesforce Data, Affecting Multiple Customers
Klue, a market intelligence SaaS provider, experienced a supply chain breach between June 11 and June 24, 2026, which led to the compromise of OAuth tokens and subsequent data exfiltration from nearly 200 organizations. The initial compromise was achieved through the exploitation of a legacy credential within Klue's integration infrastructure, allowing attackers to harvest OAuth tokens and access connected Salesforce environments of downstream customers. Salesforce disabled the Klue Battlecards app integration on June 19, 2026, in response to unusual activity. The threat actor, identified as Icarus, exfiltrated business contact and sales data and attempted extortion. A second unauthorized party later claimed access to the stolen data and launched a separate extortion campaign.
Signal context
First seen: Jun 19, 2026
Last updated: Jun 29, 2026
Status: Public signal
Key points
- Supply chain breach at Klue, a market intelligence SaaS provider.
- OAuth tokens and Salesforce data compromised from nearly 200 organizations.
- Initial compromise via exploitation of a legacy credential in Klue's integration infrastructure.
Signal analysis
BetaIt helps compare this signal with other published signals without treating the labels as final determinations.
Likely country: Location not provided
Watch internet-facing systems, credential abuse and exploit activity.
- Source type: outside the affected organization
Impact area: Confidentiality
Likely asset: User or customer data
- 1 signal in the same sector
- 97 signals with the same likely impact area
- 1 signal linked to this organization/domain
External sources
Klue OAuth breach victim list grows as Icarus hackers claim attack - Bleeping Computerhttps://www.bleepingcomputer.com/news/security/klue-oauth-breach-victim-list-grows-as-icarus-hackers-claim-attack/Public source from bleepingcomputer.com.
Cybersecurity Firms Impacted by Klue Supply Chain Attack - SecurityWeekhttps://www.securityweek.com/cybersecurity-firms-impacted-by-klue-supply-chain-attack/Public source from securityweek.com.
Scope of Salesforce Attacks Expands as Icarus Leaks Data - Cyber Recapshttps://cyberrecaps.com/news/cybersecurity-news-june-24-2026/Public source from cyberrecaps.com.
LastPass hit by new data breach - 4 steps you should take now | ZDNEThttps://www.zdnet.com/article/lastpass-new-data-breach-2026-steps-to-take-now/Public source from zdnet.com.
Cybercrime Wire For Jun. 27-28, 2026. Weekend Update. WCYB Digital Radio. - YouTubehttps://www.youtube.com/watch?v=example_youtube_linkPublic source from youtube.com.
Top 5 Cybersecurity News Stories June 26, 2026 - DIESEChttps://diesec.com/top-5-cybersecurity-news-stories-june-26-2026/Public source from diesec.com.
Salesforce Disables Klue App Integration After OAuth Token Abuse Exposes Customer Datahttps://thehackernews.com/2026/06/salesforce-disables-klue-app.htmlPublic source from thehackernews.com.
Klue Supply Chain Breach Exposes OAuth Tokens and Salesforce Data in Multi-Stage Cybersecurity Incident (June 2026) - Rescanahttps://www.rescana.com/post/klue-supply-chain-breach-exposes-oauth-tokens-and-salesforce-data-in-multi-stage-cybersecurity-incident-june-2026Public source from rescana.com.
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