# CVE-2026-39915: TIM Flow < 26.0.6 CRLF Injection via rt Parameter

> Remote attackers can inject HTTP headers via the rt parameter to execute JavaScript, steal sessions, and modify credentials in TIM Flow.

- **Severity:** High 8.5 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/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:** 24 Aug 2026
- **Updated:** 1 Oct 2026
- **Also known as:** GHSA-whrv-mf4r-37rq

## What is CVE-2026-39915?

CVE-2026-39915 is a high-severity cross-site scripting vulnerability in TIM Flow, published on 24 Aug 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

TIM Flow before 26.0.6 contains a CRLF injection vulnerability that allows remote attackers to inject arbitrary HTTP headers and response body content by embedding unsanitized carriage return and line feed sequences in the rt URL parameter, which is reflected into Set-Cookie response headers. Attackers can craft malicious requests to induce authenticated users to execute arbitrary JavaScript in their browser context, enabling session token theft and account credential modification.

Weakness: CWE-113 (Improper Neutralization of CRLF Sequences in HTTP Headers)

## Which versions are affected by CVE-2026-39915?


## How do I fix CVE-2026-39915?

No fix has been published for CVE-2026-39915 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-39915 being exploited?

There is no known exploitation of CVE-2026-39915 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-39915 and fix it if it is affected.

What it is: CVE-2026-39915 is a high-severity cross-site scripting vulnerability in TIM Flow, published on 24 Aug 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: There is no known exploitation of CVE-2026-39915 in the wild and no public exploit code.

Affected product: TIM Flow. 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-2026-39915/ (Markdown: https://insights.sbomify.com/CVE-2026-39915/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-39915
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-39915
- OSV: https://osv.dev/vulnerability/CVE-2026-39915

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-39915/
Summaries are generated and may contain mistakes; the official description above is the record.