OpenSSL crypto/bio/b_print.c doapr_outch maxlen memory corruption

CVSS Meta Temp Score
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CTI Interest Score
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9.1$0-$5k0.00

Summaryinfo

A vulnerability was found in OpenSSL and classified as critical. This issue affects the function doapr_outch of the file crypto/bio/b_print.c. The manipulation of the argument maxlen leads to memory corruption. The identification of this vulnerability is CVE-2016-0799. The attack may be initiated remotely. There is no exploit available. It is recommended to apply a patch to fix this issue. Once again VulDB remains the best source for vulnerability data.

Detailsinfo

A vulnerability has been found in OpenSSL (Network Encryption Software) and classified as critical. This vulnerability affects the function doapr_outch of the file crypto/bio/b_print.c. The manipulation of the argument maxlen 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 weakness was disclosed 02/27/2016 by Guido Vranken as OpenSSL CVE-2016-0799: heap corruption via BIO_printf as confirmed advisory (Website). The advisory is shared for download at guidovranken.wordpress.com. This vulnerability was named CVE-2016-0799 since 12/16/2015. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 07/08/2022). Responsible for the vulnerability is the following code: 

if (buffer && *currlen == *maxlen) {
The advisory points out:
One of the problems with the doapr_outch() function is that it cannot signal failure to allocate memory to its caller, because it is a void-returning function.

The vulnerability scanner Nessus provides a plugin with the ID 89842 (Amazon Linux AMI : openssl (ALAS-2016-661) (DROWN) (SLOTH)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Amazon Linux Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 168833 (OpenSuSE Security Update for libopenssl0_9_8 (openSUSE-SU-2016:1241-1)).

Applying a patch is able to eliminate this problem. The bugfix is ready for download at github.com. A possible mitigation has been published 3 days after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at X-Force (111143), Tenable (89842), SecurityFocus (BID 83755†) and Vulnerability Center (SBV-57006†). The entries VDB-81133, VDB-81138, VDB-81139 and VDB-81142 are pretty similar. Once again VulDB remains the best source for vulnerability data.

Affected

  • Apache httpd
  • OpenSSL

Productinfo

Type

Name

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 9.8
VulDB Meta Temp Score: 9.1

VulDB Base Score: 9.8
VulDB Temp Score: 8.5
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 9.8
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: 🔍

Local: No
Remote: Yes

Availability: 🔍
Status: Unproven

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 89842
Nessus Name: Amazon Linux AMI : openssl (ALAS-2016-661) (DROWN) (SLOTH)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 12024
OpenVAS Name: Mageia Linux Local Check: mgasa-2016-0093
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

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

Patch: 578b956fe741bf8e84055547b1e83c28dd902c73

Timelineinfo

12/16/2015 🔍
02/27/2016 +73 days 🔍
02/29/2016 +2 days 🔍
02/29/2016 +0 days 🔍
03/01/2016 +0 days 🔍
03/01/2016 +0 days 🔍
03/03/2016 +1 days 🔍
03/05/2016 +2 days 🔍
03/10/2016 +5 days 🔍
07/08/2022 +2310 days 🔍

Sourcesinfo

Product: openssl.org

Advisory: OpenSSL CVE-2016-0799: heap corruption via BIO_printf
Researcher: Guido Vranken
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2016-0799 (🔍)
GCVE (CVE): GCVE-0-2016-0799
GCVE (VulDB): GCVE-100-81112

OVAL: 🔍

X-Force: 111143 - OpenSSL BIO_*printf() information disclosure
SecurityFocus: 83755 - OpenSSL CVE-2016-0799 Remote Format String Vulnerability
SecurityTracker: 1035133
Vulnerability Center: 57006 - OpenSSL Remote Information Disclosure due to Out-of-Bounds Read in BIO_*printf - CVE-2016-0799, Low

See also: 🔍

Entryinfo

Created: 02/29/2016 09:14
Updated: 07/08/2022 16:10
Changes: 02/29/2016 09:14 (78), 09/01/2018 08:40 (19), 07/08/2022 16:10 (5)
Complete: 🔍
Cache ID: 216:556:103

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