Microsoft Edge Chakra JIT BailOutOnTaggedValue memory corruption

CVSS Meta Temp Score
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CTI Interest Score
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5.8$0-$5k0.00

Summaryinfo

A vulnerability identified as critical has been detected in Microsoft Edge. The affected element is the function BailOutOnTaggedValue of the component Chakra JIT. Performing a manipulation results in memory corruption. This vulnerability is known as CVE-2017-11839. Remote exploitation of the attack is possible. Furthermore, an exploit is available. It is recommended to apply a patch to fix this issue.

Detailsinfo

A vulnerability, which was classified as critical, was found in Microsoft Edge (Web Browser) (affected version not known). This affects the function BailOutOnTaggedValue of the component Chakra JIT. The manipulation with an unknown input leads to a memory corruption vulnerability. CWE is classifying the issue as CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. This is going to have an impact on confidentiality, integrity, and availability.

The bug was discovered 11/14/2017. The weakness was published 11/14/2017 by lokihardt with Google Project Zero as KB4048954 as confirmed security update guide (Website). It is possible to read the advisory at portal.msrc.microsoft.com. This vulnerability is uniquely identified as CVE-2017-11839 since 07/31/2017. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. It demands that the victim is doing some kind of user interaction. Technical details and a public exploit are known. The advisory points out:

A remote code execution vulnerability exists in the way that the scripting engine handles objects in memory in Microsoft Edge. The vulnerability could corrupt memory in such a way that an attacker could execute arbitrary code in the context of the current user. An attacker who successfully exploited the vulnerability could gain the same user rights as the current user. If the current user is logged on with administrative user rights, an attacker who successfully exploited the vulnerability could take control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.

A public exploit has been developed by Google Security Research and been published 2 weeks after the advisory. The exploit is shared for download at exploit-db.com. It is declared as proof-of-concept. We expect the 0-day to have been worth approximately $25k-$100k. The vulnerability scanner Nessus provides a plugin with the ID 104552 (KB4048956: Windows 10 LTSB November 2017 Cumulative Update), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Windows : Microsoft Bulletins and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 91413 (Microsoft Edge Security Update for November 2017). The code used by the exploit is:

function opt2(inlinee, v) {
    if (v > 0) {
        inlinee();
    } else {
        inlinee.x = 1.1;
    }
}
 
function opt() {
    opt2(2.3023e-320, null);
}
 
function main() {
    opt2(() => {}, 1);  // feed a function to the profiler
 
    for (let i = 0; i < 10000; i++) {
        opt();
    }
}

Applying the patch KB4048954 is able to eliminate this problem. The bugfix is ready for download at catalog.update.microsoft.com. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Exploit-DB (43180), Tenable (104552) and SecurityFocus (BID 101735†). Similar entries are available at VDB-109334, VDB-109336, VDB-109337 and VDB-109338. Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.0
VulDB Meta Temp Score: 5.8

VulDB Base Score: 6.3
VulDB Temp Score: 5.7
VulDB Vector: 🔍
VulDB Reliability: 🔍

Vendor Base Score (Microsoft): 4.2
Vendor Vector (Microsoft): 🔍

NVD Base Score: 7.5
NVD Vector: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Memory corruption
CWE: CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Access: Public
Status: Proof-of-Concept
Author: Google Security Research
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 104552
Nessus Name: KB4048956: Windows 10 LTSB November 2017 Cumulative Update
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 880598
OpenVAS Name: Microsoft Windows Multiple Vulnerabilities (KB4048956)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Exploit-DB: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍
Exploit Delay Time: 🔍

Patch: KB4048954

Timelineinfo

07/31/2017 🔍
11/14/2017 +106 days 🔍
11/14/2017 +0 days 🔍
11/14/2017 +0 days 🔍
11/14/2017 +0 days 🔍
11/14/2017 +0 days 🔍
11/14/2017 +0 days 🔍
11/15/2017 +1 days 🔍
11/27/2017 +12 days 🔍
11/27/2017 +0 days 🔍
12/14/2025 +2939 days 🔍

Sourcesinfo

Vendor: microsoft.com

Advisory: KB4048954
Researcher: Lokihardt (lokihardt)
Organization: Google Project Zero
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2017-11839 (🔍)
GCVE (CVE): GCVE-0-2017-11839
GCVE (VulDB): GCVE-100-109335

OVAL: 🔍

SecurityFocus: 101735 - Microsoft Edge Scripting Engine CVE-2017-11839 Remote Memory Corruption Vulnerability
SecurityTracker: 1039780

scip Labs: https://www.scip.ch/en/?labs.20161013
See also: 🔍

Entryinfo

Created: 11/15/2017 09:34
Updated: 12/14/2025 18:33
Changes: 11/15/2017 09:34 (97), 12/11/2019 21:03 (7), 01/23/2021 11:17 (3), 01/23/2021 11:24 (1), 12/14/2025 18:33 (15)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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