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
Notes Not Saving
Hello, My notes are continuously not saving. I make sure to save them, I know the process to save them. It is not operator error. I go back into a Leads profile a while later and do not see the previous notes that I have made. I then have to go back and do unnecessary research that would have been in the notes in the first place. Not a good experience and it is frustrating. Slows me down and makes me do unnecessary work. Please resolve. As a quick heads up, deleting cookies is not a fix
Prefill form with CRM/Campaigns
I created a form in zForms and created prefill fields. I added this to the CRM and selected the fields so when sending from the CRM, the form works great. However, I want to use the same form in Campaigns and I want it to pull the data from CRM (which
Triggering a campaign automation from a Form
I used Forms to create a lead form that is accessed by a button on my website. The field information flows into the CRM. However, I am trying to figure out how to use Campaign automations to start a workflow (series of campaign emails) that is triggered
Employee Appraisal Applicability - Why is Date of Joining Hard-Coded?
In the new (to me, at least) Performance Appraisal Cycle wizard, it's possible to set criteria to determine for whom the appraisal process should apply. This makes sense on its face. However, one MUST use the Date of Joining criterion as a filter. Why
Formula fields
Zoho People now supports formula fields. This post illustrates it. Formula fields are fields whose value is calculated instead of being entered by the user. Using this, number, decimal and date manipulations can be done. The value of this field could be numeric or date depending on the output of the formula. In date manipulations, the result will be given in milliseconds, which you can format as per you need. The operators we support are +, - , *, /. Formula fields get recalculated automatically
Zobot operator information
I am working on a zobot that calls a plug to send data to our API. I want the response data from that API to be shown only to the operator and not the customer. I have tried writing this data out to the visitorCity field but nothing gets updated on the
Copy paste from word document deletes random spaces
Hello Dear Zoho Team, When copying from a word document into Notebook, often I face a problem of the program deleting random spaces between words, the document become terribly faulty, eventhough it is perfect in its original source document (and without
You are not a part of any org. So Campaigns permission(s) will not be granted.
I have an issue while calling the access token by my email "kessam@axisapp.com" please give me suggestions for resolving this problem!
Is it possible to use module field filters via URL parameters?
It would be really convenient if I could quickly link to a filter. For reference, this is the filter functionality I'm referring to: https://help.zoho.com/portal/en/kb/crm/customize-crm-account/advanced-filters/articles/advanced-filters For example: My
Transitioning FESCO Bill Project to Zoho Sheets and Integration Options
Hello Zoho Support, I'm considering transitioning my FESCO bill project from Google Sheets to Zoho Sheets and wanted to know if there are integration options to seamlessly migrate our existing work. You can view our platform here, any guidance would be
Credit card
Coming from another software, is it possible here to typically have credit card payment off, but independently per customer, click a box (possibly on the invoice when I go to to send) allowing that 1 allowed customer credit card payment, NOT ALL of my
Lightbox Pop-up form
I would like to embed my form using the lightbox pop up. I don't want it to load automatically. I want it to load when some clicks the button. I can see this option, however when I use the "show pop-up launch button" on the website, the button automatically
Lightbox Pop-up form
I would like to embed my form using the lightbox pop up. I don't want it to load automatically. I want it to load when some clicks the button. I can see this option, however when I use the "show pop-up launch button" on the website, the button automatically
Connecting Portals from different Zoho apps
Hi, I note that Zoho has functionality for customer portals for several of the Zoho apps, like CRM, Projects, Desk etc. Is there any way to connect these portals? It would be great if we could give our customers access to a portal in which they could
Customer Management: #5 Never Let the Customer Slip
When Rahul started Knight's Watch Consulting, his focus was simple: deliver good work and keep clients happy. He offered one-time consulting projects, monthly advisory retainers and usage-based support for growing clients. Business was steady, and customers
Deluge date time issue
The deluge function info zoho.currentdate.toString("MMM/YYYY") returns Dec 2026 instead of 2025
Zoho Projects Android and iOS app update: Mobile device permission based on user profiles
Hello everyone! We have brought in support for mobile device permissions based on the user profiles which are configured in organization level. Administrators can now configure the permissions on the web app(projects.zoho.com) by following the steps mentioned
treatment for rehires
Hello, we are aware of the fact that Zoho People at the moment does not has a provision for rejoining exited employees. But is there any quick fix or hack to this? It will be appreciated a lot.
Zoho Projects Android and iOS app update: Timesheet module is now renamed as 'Time Logs', delete option has been renamed to 'Trash'.
Hello everyone! We have now renamed the Timesheet module as Time Logs and the delete option as 'Trash' on the Zoho Projects Android and iOS app. Time Logs Android: Time Logs iOS: Trash option Android: Trash option iOS: Please update the app to the latest
Zoho Mail app update: Manage profile picture, Chinese (Traditional) language support
Hello everyone! In the latest version (v3.1.9) of the Zoho Mail app update, we have brought in support to manage profile picture. You can now set/ modify the profile picture within the app. To add a new profile picture, please follow the below steps:
Reminders for Article Approval
Is there a way to send reminders for approvers to review articles and approve/deny them? I'm not seeing that option anywhere.
Add Full-Screen Viewing for Quartz Recordings in the Client Interface
Hi Zoho Team, We would like to request an enhancement to the Zoho Quartz client interface when viewing submitted recordings. Current Limitation: When viewing a Quartz recording from the client (user) interface, there is currently no option to switch the
2025 Recap: A Year to Remember | Zoho Inventory
Important Update : Pipedrive deprecated fields no longer supported in Zoho Analytics
Dear Pipedrive users, We would like to inform you about a recent update related to your Pipedrive integration with Zoho Analytics. The Pipedrive team has deprecated certain fields from their application. You can find more details in the official Pipedrive
Product Updates in Zoho Workplace applications | November 2025
Hello Workplace Community, Let’s take a look at the new features and enhancements that went live across all Workplace applications this November. Zoho Mail Format comments easily using Slash Commands With Slash commands, you can easily format text, insert
Right-Click Pipeline to Open in New Tab
Please add the ability to right-click on a pipeline to open it in a new tab
Adjusting Physical Inventory
Not getting very far with support on this one, they say they are going to fix it but nothings happened since November. Please give this a thumbs up if you would like to see this feature or comment if you have some insight. Use Case: Inventory set to be
sync views to sheet
Im looking to sync my views aka reports in analytics to zoho sheets, when data is updated in analytics it also should be updated in sheets, till now zoho sheets only offer raw data connection and it is not enough as these reports are difficult to re-do
How to update the Status in a custom module?
Hi, I have a custom module "cm_payment_registry" in Billing, I am trying to change the status which is "Draft" with: array = {"custom_status":"Approved"}; zoho.billing.update("cm_payment_registry",organization.get("organization_id"), XXXXXXXXXXXXXX, array,"connectionname");
Replace Zoho Invoice with QuickBooks
We are implementing Zoho FSM for a cleaning business in the US with 50+ field workers. This business has been using Quickbooks for accounting for decades and will not migrate to Zoho Books. A major issue in the integration is the US sales tax calculation.
2025 Highlights: A Year of Steady Progress and Significant Developments
As we come to the end of 2025, let's take a moment to reflect on the significant progress and developments we've made to improve your travel and expense management. In the Spotlight Introducing Online Booking (US edition only - Early access) Enable online
Function #42: Show the actual rate of items on invoices
Hello everyone, and welcome back to our series! In Zoho Books, you have the ability to create Price Lists, wherein you can mark up and mark down the item rates by a specific percentage or set custom rates. Generally, when you apply a price list to an
Ability to Set Text Direction for Individual Cells in Zoho Sheet
Dear Zoho Sheet Team, We hope you are doing well. We would like to request an enhancement in Zoho Sheet that allows users to set the text direction (right-to-left or left-to-right) for individual cells, similar to what is available in Google Sheets. Use
Warehouse fast processing
Hey guys, would anyone be interested in something like the attached image ? If there's any interest I'd be willing to develop it further for others to use, it's much faster than using Zohos native solutions, it can part pack, pack in full, part ship,
Can I create a CODE 128 custom field for my items in Zoho Inventory and then use it for generating Sales Orders?
Can anyone helps me, I don't want to use the SKU code for scanning my products. Because all my products have a CODE-128 label attached.
Start/Stop Timmer in Chrome Extension
The chrome extension is great and allows you to do allot however one of the most common things employees working on projects need to do is track their time. Having an easy start/stop timer to track time would be great.
Invalid collection string
I haven't changed anything in one of my functions. I'm trying to run it manually and suddenly "Invalid collection string" appears. My code has 6 lines and the error says that the error is on 7th line. Why? What does this error mean? Nothing has been changed
Zoho Directory 2025: New Features | Security Enhancements | Enriched UI
Hello everyone, Greetings from the Zoho Directory team! 2025 has been a highly successful year for Zoho Directory. We are delighted to introduce a fresh set of features, an enriched UI, and major product enhancements. These updates aim to deliver a smoother
zoho people 5 report
How do I customize my report in Zoho People Report? I understand that I can get the results of multi-table queries through SQL join statements, but I don't know the relationship between each table. I tried to create a report using Attendance User Report
Leave Report Emailed Weekly
I am wondering if someone knows how to have a report generated either weekly or monthly or both for department heads and ownership of upcoming employee leave. For instance, it would be nice to get an emailed report on Friday for the upcoming week of who
Next Page