# CVE-2026-62642: Denial of service in Webmail

> An attacker can cause a denial of service by sending an email with a malicious TNEF attachment, affecting Roundcube Webmail users.

- **Severity:** Medium 4.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L`)
- **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:** Yes
- **Published:** 14 Jul 2026
- **Updated:** 14 Jul 2026
- **Also known as:** DEBIAN-CVE-2026-62642, GHSA-345h-r9m2-jr4p, UBUNTU-CVE-2026-62642

## What is CVE-2026-62642?

CVE-2026-62642 is a medium-severity denial of service vulnerability in Roundcube Webmail, published on 14 Jul 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

In Roundcube Webmail before 1.6.17 and 1.7.x before 1.7.2, an infinite loop was discovered in the TNEF decoder, which may lead to denial of service upon opening an email with a TNEF attachment.

Weakness: CWE-835 (Loop with Unreachable Exit Condition)

## Which versions are affected by CVE-2026-62642?

It affects 1 product.


Products: Roundcube Webmail.

## How do I fix CVE-2026-62642?

Upgrade to a fixed version.

## Is CVE-2026-62642 being exploited?

There is no known exploitation of CVE-2026-62642 in the wild and no public exploit code.

## Other vulnerabilities in Roundcube Webmail

- [CVE-2024-42009](https://insights.sbomify.com/CVE-2024-42009/): RoundCube Webmail Cross-Site Scripting (critical 9.3, exploited in the wild)
- [CVE-2025-68461](https://insights.sbomify.com/CVE-2025-68461/): RoundCube Webmail Cross-site Scripting (high 7.2, exploited in the wild)
- [CVE-2008-5619](https://insights.sbomify.com/CVE-2008-5619/): PHPMailer susceptible to arbitrary code execution (critical 10.0)
- [CVE-2024-37385](https://insights.sbomify.com/CVE-2024-37385/): Command injection in n/a (critical 9.8)
- [CVE-2024-42008](https://insights.sbomify.com/CVE-2024-42008/): Cross-site scripting in n/a (critical 9.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-62642 and fix it if it is affected.

What it is: CVE-2026-62642 is a medium-severity denial of service vulnerability in Roundcube Webmail, published on 14 Jul 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-2026-62642 in the wild and no public exploit code.

Affected product: Roundcube Webmail. 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-2026-62642/ (Markdown: https://insights.sbomify.com/CVE-2026-62642/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-62642
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-62642
- OSV: https://osv.dev/vulnerability/CVE-2026-62642

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-62642/
Summaries are generated and may contain mistakes; the official description above is the record.