# CVE-2026-51153: Cross-site scripting in n/a

> A low-privileged attacker can inject malicious scripts via crafted task templates, leading to code execution in victim browsers.

- **Severity:** Medium 5.4 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 31 Aug 2026
- **Updated:** 1 Sep 2026
- **Also known as:** GHSA-wfcf-9h78-ggcj

## What is CVE-2026-51153?

CVE-2026-51153 is a medium-severity cross-site scripting vulnerability in n/a, published on 31 Aug 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.

### Official description

Stored Cross-Site Scripting (XSS) in TaskRunHandler.post() in web/handlers/task.py in QD 20220208 through 20250803. When a task is run via /task/<taskid>/run, the handler renders task log content (logtmp) into the HTML response using Python % string formatting without HTML encoding. logtmp is populated from the exception object or from new_env.variables.__log__, which is attacker-controlled via the template extract_variables mechanism. A low-privileged authenticated attacker can create a crafted HAR template that extracts arbitrary HTML/JavaScript into the __log__ variable via the api://util/unicode endpoint. When a victim triggers the task run, the embedded script executes in the victim browser within the QD application context.

Weakness: CWE-79 (Improper Neutralization of Input During Web Page Generation)

## Which versions are affected by CVE-2026-51153?


## How do I fix CVE-2026-51153?

No fix has been published for CVE-2026-51153 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-51153 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-51153 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-51153 and fix it if it is affected.

What it is: CVE-2026-51153 is a medium-severity cross-site scripting vulnerability in n/a, published on 31 Aug 2026. Any signed-in user can exploit it over the network, 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-2026-51153 exists.

Affected product: n/a. 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-2026-51153/ (Markdown: https://insights.sbomify.com/CVE-2026-51153/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-51153
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-51153
- OSV: https://osv.dev/vulnerability/CVE-2026-51153

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-51153/
Summaries are generated and may contain mistakes; the official description above is the record.