Update to PHPMailer 5.2.21

[mbabker]

Summary of Changes

Updates PHPMailer to 5.2.21. Composer is run with 1.3.0 which explains the ClassLoader and timestamp changes.

Testing Instructions

Mail sending works

Documentation Changes Required

N/A

[yvesh]

I have tested this item ✅ successfully on 16e7dec

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_{This comment was created with the J!Tracker Application at issues.joomla.org/tracker/joomla-cms/13388.}

[jeckodevelopment]

I have tested this item ✅ successfully on 16e7dec

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_{This comment was created with the J!Tracker Application at issues.joomla.org/tracker/joomla-cms/13388.}

[jeckodevelopment]

RTC

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_{This comment was created with the J!Tracker Application at issues.joomla.org/tracker/joomla-cms/13388.}

[mbabker]

It's fine as is. This declares that any PHPMailer version on the current major series greater than or equal to this one is fine. It'll allow anything >=5.2.20 && <6.0.

[smz]

I think this is important enough to justify a quick fix release...

[mbabker]

No, it's not. See https://developer.joomla.org/security-centre/668-20161205-phpmailer-security-advisory.html and associated references.

[Bakual]

I think this is important enough to justify a quick fix release...

See https://developer.joomla.org/security-centre/668-20161205-phpmailer-security-advisory.html
No action required for Joomla as the vulnerability isn't useable in core.

edit: Michael was faster 😄

[smz]

@mbabker & @Bakual: OK, thanks, I trust your judgement...