PHP SSRF

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SSRF PHP functions

Baadhi ya kazi kama file_get_contents(), fopen(), file(), md5_file() zinakubali URLs kama pembejeo ambazo zitafuatwa, hivyo kufanya uwezekano wa udhaifu wa SSRF ikiwa mtumiaji anaweza kudhibiti data:

file_get_contents("http://127.0.0.1:8081");
fopen("http://127.0.0.1:8081", "r");
file("http://127.0.0.1:8081");
md5_file("http://127.0.0.1:8081");

Wordpress SSRF kupitia DNS Rebinding

Kama ilivyoelezwa katika chapisho hili la blog, hata kazi ya Wordpress wp_safe_remote_get ina udhaifu wa DNS rebinding, hivyo kufanya iweze kuwa hatarini kwa mashambulizi ya SSRF. Uthibitisho mkuu inayoita ni wp_http_validate_url, ambayo inakagua kwamba protokali ni http:// au https:// na kwamba bandari ni moja ya 80, 443, na 8080, lakini ina udhaifu wa DNS rebinding.

Kazi nyingine zenye udhaifu kulingana na chapisho ni:

• wp_safe_remote_request()
• wp_safe_remote_post()
• wp_safe_remote_head()
• WP_REST_URL_Details_Controller::get_remote_url()
• download_url()
• wp_remote_fopen()
• WP_oEmbed::discover()

CRLF

Zaidi ya hayo, katika baadhi ya matukio inaweza kuwa hata inawezekana kutuma vichwa vya habari vya kiholela kupitia CRLF "udhaifu" katika kazi zilizopita:

# The following will create a header called from with value Hi and
# an extra header "Injected: I HAVE IT"
ini_set("from", "Hi\r\nInjected: I HAVE IT");
file_get_contents("http://127.0.0.1:8081");

GET / HTTP/1.1
From: Hi
Injected: I HAVE IT
Host: 127.0.0.1:8081
Connection: close

# Any of the previously mentioned functions will send those headers

Kumbuka kwamba hizi kazi zinaweza kuwa na njia nyingine za kuweka vichwa vya habari vya kiholela katika maombi, kama:

$url = "";

$options = array(
'http'=>array(
'method'=>"GET",
'header'=>"Accept-language: en\r\n" .
"Cookie: foo=bar\r\n" .  // check function.stream-context-create on php.net
"User-Agent: Mozilla/5.0 (iPad; U; CPU OS 3_2 like Mac OS X; en-us) AppleWebKit/531.21.10 (KHTML, like Gecko) Version/4.0.4 Mobile/7B334b Safari/531.21.102011-10-16 20:23:10\r\n" // i.e. An iPad
)
);

$context = stream_context_create($options);
$file = file_get_contents($url, false, $context);