I've discovered a bug in how Zoho's API Console handles the OAuth 2.0 authorization flow when the state parameter contains pipe characters (|), and I'm hoping the Zoho team can address this in a future update.
The Issue
Zoho's OAuth 2.0 implementation for server-based client applications uses the standard authorization endpoint:
https://accounts.zoho.com/oauth/v2/auth?response_type=code
&client_id=<client_id>
&scope=<scope>
&redirect_uri=<redirect_uri>
&access_type=offline
&state=<state_value>
While Zoho's
documentation does not explicitly list the
state parameter, it is a standard part of the OAuth 2.0 specification (
RFC 6749 Section 4.1.1) and is widely used for CSRF protection and maintaining application state through the authorization flow.
However, when the state parameter contains pipe characters (|), Zoho's authorization server fails to process the request correctly, preventing users from authorizing the connection. This occurs whether the pipe characters are URL-encoded (%7C) or left unencoded.
The Problem
The pipe character is a standard delimiter in multi-part state values, particularly when passing a combination of a CSRF token and a return URL. This behavior—failing on both encoded and unencoded pipe characters—is often indicative of overly restrictive input validation or a "leaky" WAF/Proxy layer that decodes parameters before the application logic can handle them.
| State Value |
As Sent in URL |
Result |
abc123xyz |
state=abc123xyz |
✓ Works correctly |
session_12345 |
state=session_12345 |
✓ Works correctly |
user|action|timestamp |
state=user|action|timestamp (unencoded pipes) |
✗ Authorization fails |
user|action|timestamp |
state=user%7Caction%7Ctimestamp (URL-encoded pipes) |
✗ Authorization fails |
user:action:timestamp |
state=user%3Aaction%3Atimestamp |
? Not tested |
Note: Pipe characters cause failures whether URL-encoded or not. Other special characters/delimiters have not been tested and may or may not exhibit similar issues.
RFC 6749 Compliance Issue
Section 4.1.1 - Authorization Request:
"state: RECOMMENDED. An opaque value used by the client to maintain state between the request and callback."
Section 4.1.2 - Authorization Response:
"state: REQUIRED if the 'state' parameter was present in the client authorization request. The exact value received from the client."
The RFC explicitly defines the state parameter as an opaque value. This means:
- The Authorization Server should not be looking "inside" or parsing the string at all
- The state value must pass through the authorization process unchanged
- Any URL-encoded characters should be handled transparently
- The exact value received must be returned to the client in the redirect
Key Point: By definition, an "opaque" parameter means the authorization server must treat it as a data blob—accepting it, storing it, and returning it without any interpretation or transformation.
Current Behavior vs Expected Behavior
| Current Behavior |
Expected Behavior (Per RFC 6749) |
1. Client sends: state=user|action|123
(or state=user%7Caction%7C123)
2. Zoho fails to parse the state parameter
3. Authorization server returns HTTP 400 Bad Request
4. User cannot authorize the connection
|
1. Client sends: state=user|action|123
2. Zoho treats state as opaque data blob
3. User authorizes the connection
4. Redirect includes the exact value received:
state=user|action|123
(or consistently encoded as sent)
|
The Current Workaround (Suboptimal)
Important: The workarounds below only apply if you have control over the client application generating the OAuth request. If you're integrating with a third-party application that sets the state parameter (e.g., integration platforms, SaaS tools, enterprise software), you have no ability to modify the state value and therefore no workaround is available. You are completely blocked from completing the OAuth flow.
For developers who do control the client application, you must avoid pipe characters entirely:
// Instead of using pipes as delimiters:
state = csrf_token + "|" + user_id + "|" + redirect_path;
// ❌ This breaks Zoho's authorization flow
// Developers must use alternative approaches:
state = csrf_token + "_SEP_" + user_id + "_SEP_" + redirect_path;
// or
state = base64_encode(json_encode({"csrf": token, "user": id, "path": path}));
// or
state = csrf_token; // Store other data server-side keyed by CSRF token
Problems with these workarounds:
- Requires refactoring existing codebases that use pipe delimiters
- Base64 encoding increases state parameter length significantly, risking URL length limits (particularly in older browsers and some enterprise proxies which enforce ~2000 character limits)
- Server-side storage approach adds complexity, database overhead, and potential race conditions
- Inconsistent with how the same code works with other OAuth providers (Google, Microsoft, etc.)
- Developers may not discover this issue until production deployment
- Custom delimiters (like
_SEP_) are non-standard and may conflict with actual data values
What Should Happen Instead
Proposed Solution:
Zoho's authorization server should properly handle URL-encoded pipe characters (%7C) in the state parameter, as required by RFC 6749. The state value must be treated as an opaque data blob.
Technical Requirement: Treat state as a Data Blob
| 1. Input |
Accept %7C (and other encoded characters) as valid parts of the query string without triggering validation errors or WAF rules |
| 2. Persistence |
Store the string exactly as received during the user's login/consent session—do not decode, parse, or transform |
| 3. Output |
Append the exact string back to the redirect_uri without additional transformations that might strip or corrupt the delimiters |
This approach:
- Complies with RFC 6749's requirement to return "the exact value received"
- Follows the same behavior as other major OAuth providers
- Requires no changes from client applications
- Unblocks third-party integrations that cannot modify their state format
Real-World Impact
This limitation affects any integration where:
- Third-party applications set the state parameter and cannot be modified (integration platforms, SaaS connectors, enterprise software)
- Multi-tenant applications need to encode tenant ID and return URL in state
- CSRF protection implementations combine security tokens with application state
- Single Sign-On flows need to preserve original request context
- Migration projects from other OAuth providers that used pipe delimiters
Critical Blocker: When the state parameter originates from a third-party system outside your control, there is no workaround available. The integration is completely impossible until this is fixed.
Security Note: The state parameter is critical for CSRF protection in OAuth flows. Forcing developers to change their state encoding approach may inadvertently introduce security vulnerabilities if not handled carefully.
Request to Zoho Team
Can this be addressed in a future update?
This is a standards compliance issue that impacts developers integrating with Zoho's API. For those who control their client application, the current implementation forces unnecessary workarounds. For those integrating third-party applications, the situation is worse:
1. Custom development
Refactor code to avoid pipe characters, creating Zoho-specific OAuth handling
|
2. Third-party integrations
No workaround possible - integration is completely blocked
|
Users should not be blocked from integrating with Zoho due to non-standard OAuth implementation.
Community Input Requested: Has anyone else encountered this issue? Are there other special characters that cause similar problems with Zoho's OAuth implementation?
📚 Documentation References:
Recent Topics
Ability to Edit Ticket Subject when Splitting a Ticket
Often someone will make an additional or new request within an existing ticket that requires we split the ticket. The annoying part is that the new ticket maintains the subject of the original ticket after the split so when the new ticket email notification
[Free Webinar] Environments in Zoho Creator - Creator Tech Connect
Hello Everyone, We’re delighted to kick off the 2026 edition of the Zoho Creator Tech Connect Series and are excited to continue this learning journey with you. The Creator Tech Connect series is a free monthly webinar featuring deep-dive technical sessions
Zoho Voice API SMS
I made a post request in Zapier to try to send an SMS. Authentication appears to be configured correctly. I followed the documentation and I'm getting a 400 Error "Internal Server Error". Not helpful at all. Anyways, I could not find any information on
How do I change (error) display messages
Hi! I would like to edit display messages like "invalid entries" and "enter a value for Nome" and so on into Italian language messages. How can I do that? Already tried on Validate on form submit. Where I am failing? Thanks in advance.
Record Overseas Transactions Along with CC charges
Hi All, We receive payments via stripe in multiple currencies and stripe takes around 2.5% fees. The amount is settled in INR into our local bank. What should be the currency of the income account used for Stripe payments? Here is a sample flow that we
Easier onboarding for new users with stage descriptions
Greetings, I hope all of you are doing well. We're happy to announce a recent enhancement we've made to Bigin. You can now add descriptions to the stages in your pipeline. Previously, when creating a pipeline, you could only add stages. With this update,
Pieds de page personnalisé - Document Zoho Writer
Bonjour à tous, Je rencontre un souci avec l’ajout d’un pied de page personnalisé dans un document Zoho Writer. Je souhaite insérer les informations de mon entreprise (notamment un logo + adresse) dans le pied de page. Le problème, c’est que lorsque j’ajoute
Credit card transactions are backwards after importing statements
I am new to Zoho Books so I'm importing my firm's bank and credit card statements in. My credit card statements have a single column with negative numbers so that is the option I chose. But when I went to categorize the credit card transactions, I can
Permissions on Views
Having the option of any agent creating custom views is firing back and got a situation where there are a hundred different views across the team and tickets are not being dealt in the most efficient of ways. Tickets seems to be missed by some agents,
Function #8: Add additional charges to invoices
Here goes one of the highly sought-after custom functions in Zoho Books. If you find yourself needing to apply additional charges to customers on their invoices (say credit card surcharges, or fuel charges applicable to customers from a certain region,
VIsual maindmaps in Zoho notebook Ai
Can I create and export VIsual maindmaps in Zoho notebook Ai
1stDibs Integration to Zoho Inventory
Hello is it possible to integrate my Zoho inventory and 1stDibs?
Community Question: Renewal vs Invoicing
This is a question for the community. Does anyone else consider there to be a difference between a subscription renewal event and sending out a recurring invoice for a subscription? For example, let's say customer XYZ purchases a 1-year subscription to
cloud console support for music websites
Hi Friends, I am not from a very technical background.. So need support from the Zoho family. I want to build a e-commerce website which is in Musical Niche. It will help people learn music & play instruments of all types. There are a few players in the market like Chordify , Guitaa, Guitar Dashboard, ChordU & few others. But I all these websites allow only a few instruments to play. So I want to build a better website than the one I mentioned. So wnated to know what UI & AI should I use so that
Scheduled Reports - Do not send empty report
Hello, We are intensively using reports in the CRM, especially for sales managers. When data is empty, they still receive an email. Can you add an option to avoid sending the report when data is empty?
Is Zoho One Desktop more secure than Zoho One Web SaaS?
Is Zoho One Desktop more secure than using Zoho One in browser? Inherently, it seems desktop would be unless you don't do things like share your pw or leave pc on. I am concerned about data being on the cloud or someone else's server and database.
Reminder Settings - Time Tracker
On the time tracker in Reminder Settings I created a reminder according to the Zoho manual. But a manager asked me to change the message that goes in the email. Is it possible to change the message? I didn't find that in the Zoho manual. Another question: I configured to receive the reminder everyone who logged in less than 40 hours. Does Zoho consider less than 40 hours of the current week or the whole month? Another situation, I put it so that I and another specific user would receive the notification,
Create Item group from a composite Item
I have applied my mind for hours but cannot figure this out. Can you have a composite item in an item group?. E.g. We bundle different color and size SKU's together as composite items. Also Using composite items as Bill of Materials. We want to create
Main difference of Zoho Recruit Corporte version and Staffing HR vesion
Hi Zoho, I need help to fully understand what is the main key point differences of Recruit Corporate version versus the Staffing HR version? We are currently using Corporate HR version and we are looking on having an insightful automated reporting, does
Out of Stock items showing in Commerce
I have over 6000 items and most are not in stock, but all items are showing up in Commerce whether they are inventory or not. What option or feature can you use to hide items in Commerce at zero or negative quantities? I currently am using Commerce for
Is it possible to transfer data from one related list to another within the same module ?
In the Leads module, there is an existing default Product related list that already contains data. Recently, I added a custom multi-lookup field, which created a new related list in the same Leads module. Now, I need to move the existing data from the
How to implement new online payment gateway?
Hello, Can you tell me how to proceed to implement my local payment gateway? DIBS has an open avaiable API that should be easy to implement into ZOHO BOOKS. http://tech.dibspayment.com/dibs_payment_window
Formula working in MS Excel , is not working in Zoho Sheets, Filter fuction which is working in MS sheets per the attached workbook / Daily update.
Filter function , which is working in MS Excel is not working in Zoho sheets. Please help on function of filter of particular class sheets and extract students name who has more than 3.5 hours of study hours on particular day depending on date in D7 cell.
New in Smart Prompt: Record Assistant for contextual assistance, and support for new AI models
Smart Prompt helps teams stay informed and move faster by providing relevant suggestions where work happens in CRM. With this update, Smart Prompt becomes more adaptable to your organization’s AI preferences. You can now choose which Large Language Model
Improved Integration Failure Information (And Notification Options)
Hi, When an attachment service for example fails, you just get "Field x - Error", I can check the field it is failing on and find nothing wrong, same file size, type, dimensions, etc. so more information as to the actual issue would be helpful. And an
Change User Role in a Form
Hi, When in a form, it would be good (And consistent) to be able to change the user role/permission like you can with Shared Reports, All Entries or the actual User itself, rather than having to delete the users permission and then add it back again with
Reassign Partially Saved Entries
Hi, I would like to be able to go to Partially Saved Entries and like the option to delete them I would like the option to multi-select and be able to reassign them to another user to complete (Such as when a user has left the company). Thanks Dan
Increase the "Maximum Saved Entries per User" Options Limit
Hi, You can create lots of saved entries, yet the Limit when you apply one is 25, we may often expect 32 to be in draft, and therefore want to enforce that, can we increase the limit of this field from 25 to 100 (As you can just turn it off and have more
Product Updates in Zoho Workplace applications | December 2025
Hello Workplace Community, Let’s take a look at the new features and enhancements that went live across all Workplace applications this December. Zoho Mail Block emails without notifying the sender Block emails without sending a rejection notification
Zoho CRM for Gmail Extension Not Working in Brave Browser?
Is anyone able to get the Zoho CRM Chrome Extension working in the Brave browser? They're both built on the Chromium platform and every other Chrome Extension works with the exception of Zoho CRM for Gmail so any ideas here?
Set Frozen Cells in the Report Settings
Hi, It would be nice to be able to set the frozen cells in the report Settings, and have an option if this is fixed or can be changed after loading (On the next load it still goes back to the Settings). Thanks Dan
Microsoft Teams now available as an online meeting provider
Hello everyone, We're pleased to announce that Zoho CRM now supports Microsoft Teams as an online meeting provider—alongside the other providers already available. Admins can enable Microsoft Teams directly from the Preferences tab under the Meetings
Tip of the week #26: Import/ Export calendars in Zoho Calendar.
Any calendar on the web or calendars that you create in any other calendar application can be imported in to Zoho Calendar. This will help you to add the events from the calendars that you import to your Zoho Calendar. You also have the option to export
Add Zoho Forms to Zoho CRM Plus bundle
Great Zoho apps like CRM and Desk have very limited form builders when it comes to form and field rules, design, integration and deployment options. Many of my clients who use Zoho CRM Plus often hit limitations with the built in forms in CRM or Desk and are then disappointed to hear that they have to additionally pay for Zoho Forms to get all these great forms functionalities. Please consider adding Zoho Forms in the Zoho CRM Plus bundle. Best regards, Mladen Svraka Zoho Certified Consultant and
Social icons, open in new tab?
Hello, I have two social icons on my footer, Facebook and Psychology Today. Clicking on the Facebook icon opens a new tab, the Psychology Today icon does not. I would like them both to open a new tab. Am I missing a setting somewhere?
Real-Time Screen Annotation During Zoho Cliq Screen Sharing
Hi Zoho Support Team, Hope you're doing well. We’d like to request the addition of real-time screen annotation tools during screen sharing sessions in Zoho Cliq video calls. 🔍 What We're Looking For: The ability for the presenter—and optionally, other
Autofill address using smart fields mapped over the pdf document
Hi, I'm using mail merge to map smart fields onto PDF documents I plan to distribute for signing. I already have a Zoho Sign subscription. When mapping smart fields from the Employee form, I only see the permanent and current addresses which include the
How do I cap employee leave accrual
HI there, How do I cap an employee's leave accrual? The policy is that you accrue 15 days leave annually (1.25 days a month) and once you reach 15 days, you wont accrue more until you take leave. Thank you!
Open sub form from a button as a popup form
Is there a way within a form to use similar code as below to show a button in the form when clicked opens the subform for data to be added to the record being viewed in the form OpenUrl("#Form:<Customer_Delivery_Address>?<Delivery_Address>=" + input.ID,"popup
Dont have backup option in setting
Hi guys. I started using zoho book a week ago. I bought premium package yet I don't have backup option in setting. I hope anyone can help me find a solution. Thanks in advance
Next Page