Mozilla Firefox ESR/Thunderbird/Thunderbird ESR up to 52.7 UTF8 memory corruption

CVSS Meta Temp Score
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CTI Interest Score
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7.5$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as critical, has been found in Mozilla Firefox ESR, Thunderbird and Thunderbird ESR up to 52.7. This issue affects some unknown processing of the component UTF8 Handler. This manipulation causes memory corruption. This vulnerability is registered as CVE-2018-5178. Remote exploitation of the attack is possible. No exploit is available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in Mozilla Firefox ESR, Thunderbird and Thunderbird ESR up to 52.7 (Mail Client Software). It has been declared as critical. Affected by this vulnerability is an unknown functionality of the component UTF8 Handler. The manipulation with an unknown input leads to a memory corruption vulnerability. The CWE definition for the vulnerability is 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. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

A buffer overflow was found during UTF8 to Unicode string conversion within JavaScript with extremely large amounts of data. This vulnerability requires the use of a malicious or vulnerable legacy extension in order to occur. This vulnerability affects Thunderbird ESR < 52.8, Thunderbird < 52.8, and Firefox ESR < 52.8.

The bug was discovered 05/09/2018. The weakness was published 06/11/2018 with Mozilla as Bug 1443891 as confirmed bug report (Bugzilla). The advisory is shared at bugzilla.mozilla.org. This vulnerability is known as CVE-2018-5178 since 01/03/2018. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 11/26/2025).

The vulnerability was handled as a non-public zero-day exploit for at least 16 days. During that time the estimated underground price was around $5k-$25k. The vulnerability scanner Nessus provides a plugin with the ID 110109 (Oracle Linux 6 : thunderbird (ELSA-2018-1726)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Oracle Linux Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 351295 (Amazon Linux Security Advisory for thunderbird: ALAS2-2018-1032).

Upgrading eliminates this vulnerability. A possible mitigation has been published even before and not after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (110109) and SecurityFocus (BID 104138†). Similar entries are available at VDB-117589, VDB-117590, VDB-117591 and VDB-117596. If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.7
VulDB Meta Temp Score: 7.5

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 8.1
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
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NVD Base Score: 🔍

Exploitinginfo

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

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 110109
Nessus Name: Oracle Linux 6 : thunderbird (ELSA-2018-1726)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 61602
OpenVAS Name: Debian LTS Advisory ([SECURITY] [DLA 1376-1] firefox-esr security update)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Timelineinfo

01/03/2018 🔍
05/09/2018 +126 days 🔍
05/09/2018 +0 days 🔍
05/25/2018 +16 days 🔍
05/25/2018 +0 days 🔍
06/11/2018 +16 days 🔍
06/11/2018 +0 days 🔍
06/12/2018 +1 days 🔍
11/26/2025 +2724 days 🔍

Sourcesinfo

Vendor: mozilla.org

Advisory: Bug 1443891
Organization: Mozilla
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2018-5178 (🔍)
GCVE (CVE): GCVE-0-2018-5178
GCVE (VulDB): GCVE-100-119365

OVAL: 🔍

SecurityFocus: 104138 - Mozilla Firefox ESR Remote Memory Corruption and Buffer Overflow Vulnerabilities
SecurityTracker: 1040898

See also: 🔍

Entryinfo

Created: 06/12/2018 10:19
Updated: 11/26/2025 08:20
Changes: 06/12/2018 10:19 (78), 02/18/2020 09:54 (5), 03/22/2023 14:29 (4), 11/26/2025 08:20 (15)
Complete: 🔍
Cache ID: 216::103

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