CVE-2021-3712 (High) detected in OpenSSLOpenSSL_1_1_1g

[mend-bolt-for-github[bot]]

CVE-2021-3712 - High Severity Vulnerability

Vulnerable Library - OpenSSLOpenSSL_1_1_1g

TLS/SSL and crypto library

Library home page: https://github.com/OpenSSL/OpenSSL.git

Found in HEAD commit: 0849a3fd192d57f5888368340225f0e18d2de72b

Found in base branch: master

Vulnerable Source Files (1)

/crypto/ec/ec_asn1.c

Vulnerability Details

ASN.1 strings are represented internally within OpenSSL as an ASN1_STRING structure which contains a buffer holding the string data and a field holding the buffer length. This contrasts with normal C strings which are repesented as a buffer for the string data which is terminated with a NUL (0) byte. Although not a strict requirement, ASN.1 strings that are parsed using OpenSSL's own "d2i" functions (and other similar parsing functions) as well as any string whose value has been set with the ASN1_STRING_set() function will additionally NUL terminate the byte array in the ASN1_STRING structure. However, it is possible for applications to directly construct valid ASN1_STRING structures which do not NUL terminate the byte array by directly setting the "data" and "length" fields in the ASN1_STRING array. This can also happen by using the ASN1_STRING_set0() function. Numerous OpenSSL functions that print ASN.1 data have been found to assume that the ASN1_STRING byte array will be NUL terminated, even though this is not guaranteed for strings that have been directly constructed. Where an application requests an ASN.1 structure to be printed, and where that ASN.1 structure contains ASN1_STRINGs that have been directly constructed by the application without NUL terminating the "data" field, then a read buffer overrun can occur. The same thing can also occur during name constraints processing of certificates (for example if a certificate has been directly constructed by the application instead of loading it via the OpenSSL parsing functions, and the certificate contains non NUL terminated ASN1_STRING structures). It can also occur in the X509_get1_email(), X509_REQ_get1_email() and X509_get1_ocsp() functions. If a malicious actor can cause an application to directly construct an ASN1_STRING and then process it through one of the affected OpenSSL functions then this issue could be hit. This might result in a crash (causing a Denial of Service attack). It could also result in the disclosure of private memory contents (such as private keys, or sensitive plaintext). Fixed in OpenSSL 1.1.1l (Affected 1.1.1-1.1.1k). Fixed in OpenSSL 1.0.2za (Affected 1.0.2-1.0.2y).

Publish Date: 2021-08-24

URL: CVE-2021-3712

CVSS 3 Score Details (7.4)

Base Score Metrics: - Exploitability Metrics: - Attack Vector: Network - Attack Complexity: High - Privileges Required: None - User Interaction: None - Scope: Unchanged - Impact Metrics: - Confidentiality Impact: High - Integrity Impact: None - Availability Impact: High

For more information on CVSS3 Scores, click here.

Suggested Fix

Type: Upgrade version

Origin: https://www.openssl.org/news/secadv/20210824.txt

Release Date: 2021-08-24

Fix Resolution: OpenSSL - 1.1.1l

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[mend-bolt-for-github[bot]]

:heavy_check_mark: This issue was automatically closed by Mend because the vulnerable library in the specific branch(es) was either marked as ignored or it is no longer part of the Mend inventory.

[mend-bolt-for-github[bot]]

:information_source: This issue was automatically re-opened by Mend because the vulnerable library in the specific branch(es) has been detected in the Mend inventory.