# CVE-2018-25334: Zechat 1.5 Cross-Site Request Forgery (CSRF) via hashtag parameter

> Attackers can bypass CSRF protections in Zechat to modify user data via a crafted hashtag parameter.

- **Severity:** Medium 5.3 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 17 May 2026
- **Updated:** 24 May 2026
- **Also known as:** GHSA-j92p-x5jx-887r

## What is CVE-2018-25334?

CVE-2018-25334 is a medium-severity vulnerability in Bylancer Zechat, published on 17 May 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

Zechat 1.5 contains a Cross-Site Request Forgery (CSRF) vulnerability that allows an attacker to change a user's information by bypassing anti-CSRF protections. The application uses a CSRF token, but an attacker can use the hashtag parameter to inject an encoded payload and bypass the CSRF protection, allowing for unauthorized changes to user data. This can be exploited by tricking a user into submitting a crafted form or by using a script to obtain and set the CSRF token.

Weakness: CWE-352 (Cross-Site Request Forgery)

## Which versions are affected by CVE-2018-25334?


## How do I fix CVE-2018-25334?

No fix has been published for CVE-2018-25334 yet. Limit exposure of the affected software until one is available.

## Is CVE-2018-25334 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2018-25334 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2018-25334 and fix it if it is affected.

What it is: CVE-2018-25334 is a medium-severity vulnerability in Bylancer Zechat, published on 17 May 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2018-25334 exists.

Affected product: Bylancer Zechat. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2018-25334/ (Markdown: https://insights.sbomify.com/CVE-2018-25334/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2018-25334
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2018-25334
- OSV: https://osv.dev/vulnerability/CVE-2018-25334

---
From sbomify Insights: https://insights.sbomify.com/CVE-2018-25334/
Summaries are generated and may contain mistakes; the official description above is the record.