CVE-2026-45068

Description

### Description Symfony Mailer selects a transport via the `MAILER_DSN` environment variable / configuration (e.g. `smtp://...`, `sendmail://...`, `native://default`). `SendmailTransport` invokes the local `sendmail` binary and supports two modes: `-bs` (speak SMTP over stdin: the default) and `-t` (read the message on stdin, pass recipients as command-line arguments). In `-t` mode, recipient addresses are appended to the sendmail command line **without a `--` end-of-options separator**. A recipient address beginning with `-` (which `Symfony\Component\Mime\Address` accepts as valid) is therefore interpreted by sendmail as a command-line option rather than an address. ### Resolution The `SendmailTransport` transport now ensure `--` is set before the list of recipients. The patch for this issue is available [here](https://github.com/symfony/symfony/commit/c45144862dc289d03952f41f6078174089a3afc6) for branch 5.4. ### Credits Symfony would like to thank Claude Mythos Preview (via Project Glasswing) for reporting the issue and providing the fix.

How to fix CVE-2026-45068

To remediate CVE-2026-45068, upgrade the affected package to a fixed version below.

• —no fix listed
• —upgrade to 5.4.52 or later
• —upgrade to 5.4.52 or later

Is CVE-2026-45068 being exploited?

No exploitation signal available. Neither CISA KEV nor a current EPSS score has been published for CVE-2026-45068.

Affected packages (3)

• from 0
• from 0, < 5.4.52
• from 0, < 5.4.52

CVSS scores

References (7)

• ADVISORYsecurity-tracker.debian.org/tracker/CVE-2026-45068
• PATCHgithub.com/symfony/symfony
• WEBgithub.com/FriendsOfPHP/security-advisories/blob/master/symfony/mailer/CVE-2026-45068.yaml
• WEBgithub.com/FriendsOfPHP/security-advisories/blob/master/symfony/symfony/CVE-2026-45068.yaml