libcURL up to 7.51.0 curl_mprintf memory corruption

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7.0	$0-$5k	0.00

Summaryinfo

A vulnerability, which was classified as critical, was found in libcURL up to 7.51.0. The affected element is the function curl_mprintf. Such manipulation leads to memory corruption. This vulnerability is listed as CVE-2016-9586. The attack may be performed from remote. There is no available exploit. You should upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, has been found in libcURL up to 7.51.0 (Network Utility Software). Affected by this issue is the function curl_mprintf. The manipulation with an unknown input leads to a memory corruption vulnerability. Using CWE to declare the problem leads to 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. Impacted is confidentiality, integrity, and availability.

The bug was discovered 12/21/2016. The weakness was presented 12/21/2016 by Daniel Stenberg as adv_20161221A as confirmed advisory (Website). The advisory is shared for download at curl.haxx.se. The public release was coordinated in cooperation with the vendor. This vulnerability is handled as CVE-2016-9586 since 11/23/2016. The attack may be launched remotely. No form of authentication is required for exploitation. There are known technical details, but no exploit is available. The advisory points out:

libcurl's implementation of the printf() functions triggers a buffer overflow when doing a large floating point output. The bug occurs when the conversion outputs more than 255 bytes. The flaw happens because the floating point conversion is using system functions without the correct boundary checks.

The vulnerability scanner Nessus provides a plugin with the ID 99134 (macOS 10.12.x < 10.12.4 Multiple Vulnerabilities (httpoxy)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family MacOS X Local Security Checks and running in the context c. The commercial vulnerability scanner Qualys is able to test this issue with plugin 176814 (Debian Security Update for curl (DLA 1568-1)).

Upgrading to version 7.52.0 eliminates this vulnerability. The upgrade is hosted for download at curl.haxx.se. Applying a patch is able to eliminate this problem. The bugfix is ready for download at curl.haxx.se. The best possible mitigation is suggested to be upgrading to the latest version. A possible mitigation has been published immediately after the disclosure of the vulnerability. The advisory contains the following remark:

In version 7.52.0, the conversion is limited to never generate a larger output than what fits in the fixed size buffer.

The vulnerability is also documented in the databases at Tenable (99134), SecurityFocus (BID 95019†) and SecurityTracker (ID 1037515†). See VDB-90449, VDB-91385, VDB-91680 and VDB-91681 for similar entries. Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• Network Utility Software

Name

• libcURL

Version

• 7.0
• 7.1
• 7.2
• 7.3
• 7.4
• 7.5
• 7.6
• 7.7
• 7.8
• 7.9
• 7.10
• 7.11
• 7.12
• 7.13
• 7.14
• 7.15
• 7.16
• 7.17
• 7.18
• 7.19
• 7.20
• 7.21
• 7.22
• 7.23
• 7.24
• 7.25
• 7.26
• 7.27
• 7.28
• 7.29
• 7.30
• 7.31
• 7.32
• 7.33
• 7.34
• 7.35
• 7.36
• 7.37
• 7.38
• 7.39
• 7.40
• 7.41
• 7.42
• 7.43
• 7.44
• 7.45
• 7.46
• 7.47
• 7.48
• 7.49
• 7.50
• 7.51.0

License

• open-source

CPE 2.3info

• 🔍
• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍
• 🔍

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.1
VulDB Meta Temp Score: 7.0

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

NVD Base Score: 8.1
NVD Vector: 🔍

CNA Base Score: 5.9
CNA Vector (Red Hat, Inc.): 🔍

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

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: 🔍
Status: Proof-of-Concept
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Nessus ID: 99134
Nessus Name: macOS 10.12.x < 10.12.4 Multiple Vulnerabilities (httpoxy)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 801105
OpenVAS Name: Apple Mac OS X Multiple Vulnerabilities-HT207922
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Exploit-DB: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

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

Upgrade: libcURL 7.52.0
Patch: curl.haxx.se

Timelineinfo

11/23/2016 🔍
12/21/2016 +28 days 🔍
12/21/2016 +0 days 🔍
12/21/2016 +0 days 🔍
12/21/2016 +0 days 🔍
12/21/2016 +0 days 🔍
12/22/2016 +1 days 🔍
03/31/2017 +99 days 🔍
04/23/2018 +388 days 🔍
10/12/2022 +1633 days 🔍

Sourcesinfo

Advisory: adv_20161221A
Researcher: Daniel Stenberg
Status: Confirmed
Confirmation: 🔍
Coordinated: 🔍

CVE: CVE-2016-9586 (🔍)
GCVE (CVE): GCVE-0-2016-9586
GCVE (VulDB): GCVE-100-94628
SecurityFocus: 95019 - cURL/libcURL CVE-2016-9586 Buffer Overflow Vulnerability
SecurityTracker: 1037515

See also: 🔍

Entryinfo

Created: 12/22/2016 11:12
Updated: 10/12/2022 14:14
Changes: 12/22/2016 11:12 (75), 07/14/2019 17:47 (15), 10/12/2022 14:04 (3), 10/12/2022 14:09 (12), 10/12/2022 14:10 (1), 10/12/2022 14:14 (1)
Complete: 🔍
Cache ID: 216::103

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