Lynx up to 2.8.8 HTML Parser use after free

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.2$0-$5k0.00

Summaryinfo

A vulnerability classified as critical has been found in Lynx up to 2.8.8. This issue affects some unknown processing of the component HTML Parser. The manipulation leads to use after free. This vulnerability is traded as CVE-2017-1000211. It is possible to initiate the attack remotely. There is no exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in Lynx up to 2.8.8 (Web Browser). It has been rated as critical. This issue affects some unknown processing of the component HTML Parser. The manipulation with an unknown input leads to a use after free vulnerability. Using CWE to declare the problem leads to CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

Lynx version 2.8.8 and older is vulnerable to a use after free in the HTML parser resulting in memory disclosure.

The bug was discovered 07/06/2017. The weakness was shared 11/17/2017 (Website). It is possible to read the advisory at lynx.invisible-island.net. The identification of this vulnerability is CVE-2017-1000211 since 11/17/2017. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. The technical details are unknown and an exploit is not publicly available.

The vulnerability was handled as a non-public zero-day exploit for at least 134 days. During that time the estimated underground price was around $0-$5k. The vulnerability scanner Nessus provides a plugin with the ID 104678 (Debian DLA-1175-1 : lynx-cur security update), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Debian Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 170586 (OpenSUSE Security Update for lynx (openSUSE-SU-2017:3198-1)).

Upgrading eliminates this vulnerability. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (104678) and SecurityFocus (BID 102180†). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.2

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

NVD Base Score: 5.3
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: Use after free
CWE: CWE-416 / 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: 104678
Nessus Name: Debian DLA-1175-1 : lynx-cur security update
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 803061
OpenVAS Name: Fedora Update for lynx FEDORA-2017-bf172b2035
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

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

Patch: github.com

Timelineinfo

07/06/2017 🔍
11/17/2017 +134 days 🔍
11/17/2017 +0 days 🔍
11/17/2017 +0 days 🔍
11/17/2017 +0 days 🔍
11/18/2017 +1 days 🔍
11/20/2017 +2 days 🔍
12/06/2017 +16 days 🔍
01/10/2023 +1861 days 🔍

Sourcesinfo

Advisory: 280a61b300a1614f6037efc0902ff7ecf17146e9
Researcher: Ned Williamson
Status: Not defined
Confirmation: 🔍

CVE: CVE-2017-1000211 (🔍)
GCVE (CVE): GCVE-0-2017-1000211
GCVE (VulDB): GCVE-100-109619
SecurityFocus: 102180 - Lynx 'HTML.c:HTML_put_string()' Function Use After Free Information Disclosure Vulnerability

Entryinfo

Created: 11/18/2017 08:50
Updated: 01/10/2023 18:11
Changes: 11/18/2017 08:50 (71), 12/08/2019 08:45 (6), 01/24/2021 11:19 (2), 01/10/2023 18:04 (4), 01/10/2023 18:11 (1)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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