Vulnerability identifier: #VU27960

Vulnerability risk: Medium

CVSSv3.1: 7.4 [CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:U/RC:C]

CVE-ID: CVE-2019-17571

CWE-ID: CWE-502

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Apache Log4j
Universal components / Libraries / Libraries used by multiple products

Vendor: Apache Foundation

Description

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to insecure input validation when processing serialized data within the SocketServer class in Log4j. A remote attacker can pass specially crafted data to the application and execute arbitrary code on the target system,  if these is a deserialization gadget listening to untrusted network traffic for log data.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

Mitigation
Cybersecurity Help is currently unaware of any official solution to address this vulnerability.

Vulnerable software versions

Apache Log4j: 1.2.1 - 1.2.17

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External links
http://lists.opensuse.org/opensuse-security-announce/2020-01/msg00022.html
http://lists.apache.org/thread.html/277b4b5c2b0e06a825ccec565fa65bd671f35a4d58e3e2ec5d0618e1@%3Cdev.tika.apache.org%3E
http://lists.apache.org/thread.html/44491fb9cc19acc901f7cff34acb7376619f15638439416e3e14761c@%3Cdev.tika.apache.org%3E
http://lists.apache.org/thread.html/479471e6debd608c837b9815b76eab24676657d4444fcfd5ef96d6e6@%3Cdev.tika.apache.org%3E
http://lists.apache.org/thread.html/564f03b4e9511fcba29c68fc0299372dadbdb002718fa8edcc4325e4@%3Cjira.kafka.apache.org%3E
http://lists.apache.org/thread.html/6114ce566200d76e3cc45c521a62c2c5a4eac15738248f58a99f622c@%3Cissues.activemq.apache.org%3E
http://lists.apache.org/thread.html/752ec92cd1e334a639e79bfbd689a4ec2c6579ec5bb41b53ffdf358d@%3Cdev.kafka.apache.org%3E
http://lists.apache.org/thread.html/8ab32b4c9f1826f20add7c40be08909de9f58a89dc1de9c09953f5ac@%3Cissues.activemq.apache.org%3E
http://lists.apache.org/thread.html/eea03d504b36e8f870e8321d908e1def1addda16adda04327fe7c125%40%3Cdev.logging.apache.org%3E
http://lists.apache.org/thread.html/r05755112a8c164abc1004bb44f198b1e3d8ca3d546a8f13ebd3aa05f@%3Cissues.zookeeper.apache.org%3E
http://lists.apache.org/thread.html/r107c8737db39ec9ec4f4e7147b249e29be79170b9ef4b80528105a2d@%3Cdev.zookeeper.apache.org%3E
http://lists.apache.org/thread.html/r189aaeaad897f7d6b96f7c43a8ef2dfb9f6e9f8c1cc9ad182ce9b9ae@%3Cjira.kafka.apache.org%3E
http://lists.apache.org/thread.html/r18f1c010b554a3a2d761e8ffffd8674fd4747bcbcf16c643d708318c@%3Cissues.activemq.apache.org%3E
http://lists.apache.org/thread.html/r2756fd570b6709d55a61831ca028405bcb3e312175a60bc5d911c81f@%3Cjira.kafka.apache.org%3E
http://lists.apache.org/thread.html/r2ce8d26154bea939536e6cf27ed02d3192bf5c5d04df885a80fe89b3@%3Cissues.activemq.apache.org%3E
http://lists.apache.org/thread.html/r2ff63f210842a3c5e42f03a35d8f3a345134d073c80a04077341c211@%3Cissues.activemq.apache.org%3E
http://lists.apache.org/thread.html/r356d57d6225f91fdc30f8b0a2bed229d1ece55e16e552878c5fa809a@%3Cissues.zookeeper.apache.org%3E
http://lists.apache.org/thread.html/r3a85514a518f3080ab1fc2652cfe122c2ccf67cfb32356acb1b08fe8@%3Cdev.tika.apache.org%3E
http://lists.apache.org/thread.html/r3c575cabc7386e646fb12cb82b0b38ae5a6ade8a800f827107824495@%3Cjira.kafka.apache.org%3E
http://lists.apache.org/thread.html/r3d666e4e8905157f3c046d31398b04f2bfd4519e31f266de108c6919@%3Cissues.activemq.apache.org%3E
http://lists.apache.org/thread.html/r48d5019bd42e0770f7e5351e420a63a41ff1f16924942442c6aff6a8@%3Ccommits.zookeeper.apache.org%3E
http://lists.apache.org/thread.html/r48efc7cb5aeb4e1f67aaa06fb4b5479a5635d12f07d0b93fc2d08809@%3Ccommits.zookeeper.apache.org%3E
http://lists.apache.org/thread.html/r4ac89cbecd9e298ae9fafb5afda6fa77ac75c78d1ac957837e066c4e@%3Cuser.zookeeper.apache.org%3E
http://lists.apache.org/thread.html/r4b25538be50126194cc646836c718b1a4d8f71bd9c912af5b59134ad@%3Cdev.tika.apache.org%3E
http://lists.apache.org/thread.html/r61590890edcc64140e0c606954b29a063c3d08a2b41d447256d51a78@%3Cissues.activemq.apache.org%3E
http://lists.apache.org/thread.html/r6236b5f8646d48af8b66d5050f288304016840788e508c883356fe0e@%3Clog4j-user.logging.apache.org%3E
http://lists.apache.org/thread.html/r681b4432d0605f327b68b9f8a42662993e699d04614de4851c35ffd1@%3Cdev.tika.apache.org%3E
http://lists.apache.org/thread.html/r696507338dd5f44efc23d98cafe30f217cf3ba78e77ed1324c7a5179@%3Cjira.kafka.apache.org%3E
http://lists.apache.org/thread.html/r6aec6b8f70167fa325fb98b3b5c9ce0ffaed026e697b69b85ac24628@%3Cissues.zookeeper.apache.org%3E
http://lists.apache.org/thread.html/r746fbc3fc13aee292ae6851f7a5080f592fa3a67b983c6887cdb1fc5@%3Cdev.tika.apache.org%3E
http://lists.apache.org/thread.html/r7bcdc710857725c311b856c0b82cee6207178af5dcde1bd43d289826@%3Cissues.activemq.apache.org%3E
http://lists.apache.org/thread.html/r8890b8f18f1de821595792b58b968a89692a255bc20d86d395270740@%3Ccommits.druid.apache.org%3E
http://lists.apache.org/thread.html/r8a1cfd4705258c106e488091fcec85f194c82f2bbde6bd151e201870@%3Cjira.kafka.apache.org%3E
http://lists.apache.org/thread.html/r8d78a0fbb56d505461e29868d1026e98c402e6a568c13a6da67896a2@%3Cdev.jena.apache.org%3E
http://lists.apache.org/thread.html/r8e3f7da12bf5750b0a02e69a78a61073a2ac950eed7451ce70a65177@%3Ccommits.zookeeper.apache.org%3E
http://lists.apache.org/thread.html/r909b8e3a36913944d3b7bafe9635d4ca84f8f0e2cd146a1784f667c2@%3Cissues.zookeeper.apache.org%3E
http://lists.apache.org/thread.html/r944183c871594fe9a555b8519a7c945bbcf6714d72461aa6c929028f@%3Cissues.zookeeper.apache.org%3E
http://lists.apache.org/thread.html/ra38785cfc0e7f17f8e24bebf775dd032c033fadcaea29e5bc9fffc60@%3Cdev.tika.apache.org%3E
http://lists.apache.org/thread.html/raedd12dc24412b3780432bf202a2618a21a727788543e5337a458ead@%3Cissues.activemq.apache.org%3E
http://lists.apache.org/thread.html/rb1b29aee737e1c37fe1d48528cb0febac4f5deed51f5412e6fdfe2bf@%3Cissues.activemq.apache.org%3E
http://lists.apache.org/thread.html/rbc45eb0f53fd6242af3e666c2189464f848a851d408289840cecc6e3@%3Ccommits.zookeeper.apache.org%3E
http://lists.apache.org/thread.html/rbdf18e39428b5c80fc35113470198b1fe53b287a76a46b0f8780b5fd@%3Cdev.zookeeper.apache.org%3E
http://lists.apache.org/thread.html/rc17d8491beee51607693019857e41e769795366b85be00aa2f4b3159@%3Cnotifications.zookeeper.apache.org%3E
http://lists.apache.org/thread.html/rc1eaed7f7d774d5d02f66e49baced31e04827a1293d61a70bd003ca7@%3Cdev.tika.apache.org%3E
http://lists.apache.org/thread.html/rc628307962ae1b8cc2d21b8e4b7dd6d7755b2dd52fa56a151a27e4fd@%3Cissues.zookeeper.apache.org%3E
http://lists.apache.org/thread.html/rca24a281000fb681d7e26e5c031a21eb4b0593a7735f781b53dae4e2@%3Cdev.tika.apache.org%3E
http://lists.apache.org/thread.html/rd5dbeee4808c0f2b9b51479b50de3cc6adb1072c332a200d9107f13e@%3Cissues.activemq.apache.org%3E
http://lists.apache.org/thread.html/rd6254837403e8cbfc7018baa9be29705f3f06bd007c83708f9a97679@%3Cissues.zookeeper.apache.org%3E
http://lists.apache.org/thread.html/rdec0d8ac1f03e6905b0de2df1d5fcdb98b94556e4f6cccf7519fdb26@%3Cdev.tika.apache.org%3E
http://lists.apache.org/thread.html/rdf2a0d94c3b5b523aeff7741ae71347415276062811b687f30ea6573@%3Ccommits.zookeeper.apache.org%3E
http://lists.apache.org/thread.html/re8c21ed9dd218c217d242ffa90778428e446b082b5e1c29f567e8374@%3Cissues.activemq.apache.org%3E
http://lists.apache.org/thread.html/rec34b1cccf907898e7cb36051ffac3ccf1ea89d0b261a2a3b3fb267f@%3Ccommits.zookeeper.apache.org%3E
http://lists.apache.org/thread.html/rf1b434e11834a4449cd7addb69ed0aef0923112b5938182b363a968c@%3Cnotifications.zookeeper.apache.org%3E
http://lists.apache.org/thread.html/rf2567488cfc9212b42e34c6393cfa1c14e30e4838b98dda84d71041f@%3Cdev.tika.apache.org%3E
http://lists.debian.org/debian-lts-announce/2020/01/msg00008.html
http://security.netapp.com/advisory/ntap-20200110-0001/
http://www.debian.org/security/2020/dsa-4686
http://www.oracle.com/security-alerts/cpuapr2020.html

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.