CVE-2019-0863 : Détail

CVE-2019-0863

7.8
/
Haute
0.52%V3
Local
2019-05-16
18h17 +00:00
2025-02-07
16h28 +00:00
CVE.org
NVD
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Descriptions du CVE

An elevation of privilege vulnerability exists in the way Windows Error Reporting (WER) handles files, aka 'Windows Error Reporting Elevation of Privilege Vulnerability'.

Informations du CVE

Faiblesses connexes

CWE-ID Nom de la faiblesse Source
CWE Other No informations.

Métriques

Métriques Score Gravité CVSS Vecteur Source
V3.1 7.8 HIGH CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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.

Local

The vulnerable component is not bound to the network stack and the attacker’s path is via read/write/execute capabilities.

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 when attacking the vulnerable component.

Privileges Required

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

Low

The attacker 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 has the ability to access only non-sensitive resources.

User Interaction

This metric captures the requirement for a human 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

The Scope metric captures whether a vulnerability in one vulnerable component impacts resources in components beyond its security scope.

Scope

Formally, a security authority is a mechanism (e.g., an application, an operating system, firmware, a sandbox environment) that defines and enforces access control in terms of how certain subjects/actors (e.g., human users, processes) can access certain restricted objects/resources (e.g., files, CPU, memory) in a controlled manner. All the subjects and objects under the jurisdiction of a single security authority are considered to be under one security scope. If a vulnerability in a vulnerable component can affect a component which is in a different security scope than the vulnerable component, a Scope change occurs. Intuitively, whenever the impact of a vulnerability breaches a security/trust boundary and impacts components outside the security scope in which vulnerable component resides, a Scope change occurs.

Unchanged

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

Base: Impact Metrics

The Impact metrics capture the effects of a successfully exploited vulnerability on the component that suffers the worst outcome that is most directly and predictably associated with the attack. Analysts should constrain impacts to a reasonable, final outcome which they are confident an attacker is able to achieve.

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.

High

There is a total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact. For example, an attacker steals the administrator's password, or private encryption keys of a web server.

Integrity Impact

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

High

There is a total loss of integrity, or a complete loss of protection. For example, the attacker is able to modify any/all files protected by the impacted component. Alternatively, only some files can be modified, but malicious modification would present a direct, serious consequence to 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 a 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 in the description of a vulnerability.

Environmental Metrics

These metrics enable the analyst to customize the CVSS score depending on the importance of the affected IT asset to a user’s organization, measured in terms of Confidentiality, Integrity, and Availability.

 [email protected]
V2 7.2 AV:L/AC:L/Au:N/C:C/I:C/A:C [email protected]

CISA KEV (Vulnérabilités Exploitées Connues)

Nom de la vulnérabilité : Microsoft Windows Error Reporting (WER) Privilege Escalation Vulnerability

Action requise : Apply updates per vendor instructions.

Connu pour être utilisé dans des campagnes de ransomware : Unknown

Ajouter le : 2021-11-02 23h00 +00:00

Action attendue : 2022-05-02 22h00 +00:00

Informations importantes
Ce CVE est identifié comme vulnérable et constitue une menace active, selon le Catalogue des Vulnérabilités Exploitées Connues (CISA KEV). La CISA a répertorié cette vulnérabilité comme étant activement exploitée par des cybercriminels, soulignant ainsi l'importance de prendre des mesures immédiates pour remédier à cette faille. Il est impératif de prioriser la mise à jour et la correction de ce CVE afin de protéger les systèmes contre les potentielles cyberattaques.

EPSS

EPSS est un modèle de notation qui prédit la probabilité qu'une vulnérabilité soit exploitée.

Score EPSS

Le modèle EPSS produit un score de probabilité compris entre 0 et 1 (0 et 100 %). Plus la note est élevée, plus la probabilité qu'une vulnérabilité soit exploitée est grande.

Percentile EPSS

Le percentile est utilisé pour classer les CVE en fonction de leur score EPSS. Par exemple, une CVE dans le 95e percentile selon son score EPSS est plus susceptible d'être exploitée que 95 % des autres CVE. Ainsi, le percentile sert à comparer le score EPSS d'une CVE par rapport à d'autres CVE.
EPSS First.org

Informations sur l'Exploit

Exploit Database EDB-ID : 46917

Date de publication : 2019-05-21 22h00 +00:00
Auteur : SandboxEscaper
EDB Vérifié : No

EDIT: Apparently this was patched earlier this month.. so whatever. Windows Error Reporting Arbitrary DACL write It can take upwards of 15 minutes for the bug to trigger. If it takes too long, closing the program, cleaning out the reportarchive folder in programdata (it may mess up the timing if there's too many reports in there as result of running our poc for too long), deleting the c:\blah folder.. etc.. might help. I guess a more determined attacker might be able to make it more reliable. It is just an insanely small window in which we can win our race, I wasn't even sure if I could ever exploit it at all. I don't see a way to use OPLOCKS to reliably win the race.. and while I can make it work fairly reliable in my VM, I need to use a "rand()" function to bruteforce a delay needed to hit the correct timing.. because this timing will vary wildly from hardware setup to setup. Overview: 1. We turn c:\programdata\microsoft\windows\wer\reportqueue into a junction point to c:\blah 2. In c:\blah we create a folder named 1_1_1_1_1, and inside we dump a .wer file and another file called test 3. We trigger the WER reporting queue task 4. When the service tries to write a DACL we delete the file "test" after it calls GetSecurityFile on it and replace it with a hardlink, on which the service will call SetSecurityFile. Bug description: The WER service will try to delete both files while not impersonating when we trigger the reporting queue task. It does extensive testing against junctions.. so we cannot abuse that. However it will write a DACL to both files, to ensure that SYSTEM has the "delete" right over them. The way this works is in two steps: 1. It calls GetFileSecurity and gets a security descriptor (or whatever the technical name is) 2. It adds some stuff to the security descriptor so SYSTEM has delete rights, and then writes it back to the file using SetFileSecurity It also closes file handles between both function calls which is convenient. This means that if between both function calls we plant a hardlink.. it will first get the security descriptor from a normal file which authenticated users can write to. It will then copy these permissions, and applies this security descriptor to a hardlink pointing to an entirely different file. The race condition is incredibly hard to win. I havn't tested on another setup.. but you definitely need multiple processor cores and you may have to wait minutes for it to work (It can take a really long time.. ). Anyway... in an LPE scenario time is not that much of an issue. A succesful run will look like this. You can see the hardlink being created after the QuerySecurityFile and before SetSecurityFile. You can also ofcourse look in IDA (wer.dll) and confirm there. The vulnerable function is: UtilAddAccessToPath Steps to reproduce: 1. Copy AngryPolarBearBug.exe and report.wer into the same folder 2. Run AngryPolarBearBug.exe After many long minutes it should stop and c:\windows\system32\drivers\pci.sys should now by writeable from non-admin. Again.. I have only tested this on both my VM and host, I don't even know if the random delay range will work on other hardware setups (it basically tries to bruteforce the correct timing).. so I hope you can repo it. EDB Note: Download ~ https://gitlab.com/exploit-database/exploitdb-bin-sploits/-/raw/main/bin-sploits/46917.zip

Products Mentioned

Configuraton 0

Microsoft>>Windows_10 >> Version -

Microsoft>>Windows_10 >> Version 1607

Microsoft>>Windows_10 >> Version 1703

Microsoft>>Windows_10 >> Version 1709

Microsoft>>Windows_10 >> Version 1803

Microsoft>>Windows_10 >> Version 1809

Microsoft>>Windows_10 >> Version 1903

Microsoft>>Windows_7 >> Version -

Microsoft>>Windows_8.1 >> Version -

Microsoft>>Windows_rt_8.1 >> Version -

Microsoft>>Windows_server_2008 >> Version r2

Microsoft>>Windows_server_2008 >> Version r2

Microsoft>>Windows_server_2012 >> Version -

Microsoft>>Windows_server_2012 >> Version r2

Microsoft>>Windows_server_2016 >> Version -

Microsoft>>Windows_server_2016 >> Version 1803

Microsoft>>Windows_server_2016 >> Version 1903

Microsoft>>Windows_server_2019 >> Version -

Références