BitTorrent Bootstrap lazy_bdecode.cpp lazy_bdecode input validation

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.4$0-$5k0.00

Summaryinfo

A vulnerability was found in BitTorrent Bootstrap. It has been classified as critical. Impacted is the function lazy_bdecode of the file lazy_bdecode.cpp. Performing a manipulation results in input validation. This vulnerability is identified as CVE-2015-5685. There is not any exploit available. To fix this issue, it is recommended to deploy a patch.

Detailsinfo

A vulnerability classified as critical has been found in BitTorrent Bootstrap (Peer-to-Peer Software) (unknown version). This affects the function lazy_bdecode of the file lazy_bdecode.cpp. The manipulation with an unknown input leads to a input validation vulnerability. CWE is classifying the issue as CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

The lazy_bdecode function in BitTorrent DHT bootstrap server (bootstrap-dht ) allows remote attackers to execute arbitrary code via a crafted packet, related to "improper indexing."

The weakness was released 07/29/2015 with Team_LPJ@BoB as ZDI-15-366 / ZDI-15-367 as confirmed advisory (ZDI). It is possible to read the advisory at zerodayinitiative.com. This vulnerability is uniquely identified as CVE-2015-5685 since 07/27/2015. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Technical details of the vulnerability are known, but there is no available exploit. The reason for this vulnerability is this part of code: 

if (start + len + 1 > end)

The vulnerability was handled as a non-public zero-day exploit for at least 107 days. During that time the estimated underground price was around $0-$5k. The vulnerability scanner Nessus provides a plugin with the ID 86022 (Debian DLA-312-1 : libtorrent-rasterbar 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.

Applying a patch is able to eliminate this problem. The bugfix is ready for download at github.com. A possible mitigation has been published 2 months after the disclosure of the vulnerability. The vulnerability will be addressed with the following lines of code:

const ptrdiff_t buff_size = end - start - 1;
if (len > buff_size)

The vulnerability is also documented in the databases at X-Force (105228) and Tenable (86022). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

Vendor

Name

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.3
VulDB Meta Temp Score: 6.4

VulDB Base Score: 7.3
VulDB Temp Score: 6.4
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

Class: Input validation
CWE: CWE-20
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Unproven

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 86022
Nessus Name: Debian DLA-312-1 : libtorrent-rasterbar security update
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 12024
OpenVAS Name: Mageia Linux Local Check: mgasa-2015-0428
OpenVAS File: 🔍
OpenVAS Family: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

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

Patch: github.com

Timelineinfo

04/13/2015 🔍
07/27/2015 +105 days 🔍
07/29/2015 +2 days 🔍
07/31/2015 +2 days 🔍
08/13/2015 +13 days 🔍
09/20/2015 +37 days 🔍
09/21/2015 +1 days 🔍
09/21/2018 +1096 days 🔍

Sourcesinfo

Advisory: ZDI-15-366 / ZDI-15-367
Organization: Team_LPJ@BoB
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2015-5685 (🔍)
GCVE (CVE): GCVE-0-2015-5685
GCVE (VulDB): GCVE-100-76851
X-Force: 105228 - BitTorrent Bootstrap lazy_bdecode code execution

Entryinfo

Created: 07/31/2015 10:32
Updated: 09/21/2018 10:25
Changes: 07/31/2015 10:32 (62), 09/21/2018 10:25 (12)
Complete: 🔍
Cache ID: 216::103

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

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