A important safety vulnerability has been found in Zendesk’s Android SDK implementation that permits attackers to carry out mass account takeovers with none consumer interplay.
The flaw, which earned a $3,000 bug bounty payout, stems from predictable token technology mechanisms that allow unauthorized entry to all Zendesk assist tickets throughout affected organizations.
Key Takeaways1. Predictable JWT tokens in Zendesk’s Android SDK enable zero-click account takeovers.2. Attackers can mass-generate tokens with out fee limits to entry all tickets and knowledge.3. Repair through the use of high-entropy secrets and techniques, imposing fee limits, and auditing cell auth.
The vulnerability exploits a basic weak spot in how the Zendesk Android SDK generates authentication tokens, combining hardcoded secrets and techniques with sequential account IDs to create predictable JWT tokens.
This design flaw permits malicious actors to systematically generate legitimate authentication tokens for any consumer account with out requiring any type of consumer interplay or social engineering.
Account Takeover Vulnerability
Voorivex’s Group studies that the vulnerability lies throughout the ZendeskHelper.g() technique, which implements a flawed token technology algorithm. The strategy creates authentication tokens utilizing a predictable formulation:
The token technology course of follows these steps:
Base String Building: REDACTED-{AccountID}-{HardcodedSecret}
SHA-1 Hash Era: The bottom string is processed by means of SHA-1 hashing
Remaining Token Format: {AccountID}_{SHA1Hash}
The important flaw emerges from two key weaknesses: the usage of a static hardcoded secret (987sdasdlkjlakdjf) that continues to be fixed throughout all installations, and sequential account IDs (getRemoteId()) that may be simply enumerated.
This mix creates a state of affairs the place attackers can generate legitimate authentication tokens for any consumer by merely iterating by means of account ID ranges.
The authentication circulate sends POST requests to /entry/sdk/jwt endpoints:
The server responds with a sound access_token that grants full entry to the sufferer’s Zendesk assist surroundings, together with the power to learn all tickets, submit new requests, and carry out any motion obtainable by means of the assist interface.
The vulnerability allows zero-click mass account takeover assaults by means of systematic token technology and validation.
Attackers can implement automated scripts to iterate by means of account ID ranges, generate corresponding tokens, and validate them towards Zendesk endpoints with out triggering fee limiting or account lockout mechanisms.
Profitable exploitation grants attackers entry to:
Full ticket histories containing delicate buyer communications
Private identifiable data (PII) inside assist conversations
Inside firm communications and assist procedures
Buyer criticism patterns and enterprise intelligence knowledge
Skill to impersonate respectable customers in assist interactions
The vulnerability impacts any group utilizing Zendesk’s Android SDK for cell assist integration, probably impacting 1000’s of firms worldwide.
This important flaw demonstrates the extreme safety dangers related to predictable authentication mechanisms and highlights the significance of implementing sturdy token technology techniques and complete safety testing all through the cell software improvement lifecycle.
Discover this Story Fascinating! Observe us on LinkedIn and X to Get Extra Instantaneous Updates.
