7.4 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:H
5.8 Medium
CVSS2
Access Vector
NETWORK
Access Complexity
MEDIUM
Authentication
NONE
Confidentiality Impact
PARTIAL
Integrity Impact
NONE
Availability Impact
PARTIAL
AV:N/AC:M/Au:N/C:P/I:N/A:P
0.005 Low
EPSS
Percentile
75.6%
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).
Author | Note |
---|---|
mdeslaur | in 1.0.2, this bug is in X509_CERT_AUX_print() list of commits below is incomplete |
OS | Version | Architecture | Package | Version | Filename |
---|---|---|---|---|---|
ubuntu | 18.04 | noarch | edk2 | < any | UNKNOWN |
ubuntu | 20.04 | noarch | edk2 | < 0~20191122.bd85bf54-2ubuntu3.3 | UNKNOWN |
ubuntu | 21.04 | noarch | edk2 | < 2020.11-4ubuntu0.1 | UNKNOWN |
ubuntu | 22.04 | noarch | edk2 | < any | UNKNOWN |
ubuntu | 16.04 | noarch | edk2 | < any | UNKNOWN |
ubuntu | 18.04 | noarch | openssl | < 1.1.1-1ubuntu2.1~18.04.13 | UNKNOWN |
ubuntu | 20.04 | noarch | openssl | < 1.1.1f-1ubuntu2.8 | UNKNOWN |
ubuntu | 21.04 | noarch | openssl | < 1.1.1j-1ubuntu3.5 | UNKNOWN |
ubuntu | 21.10 | noarch | openssl | < 1.1.1l-1ubuntu1 | UNKNOWN |
ubuntu | 22.04 | noarch | openssl | < 1.1.1l-1ubuntu1 | UNKNOWN |
launchpad.net/bugs/cve/CVE-2021-3712
nvd.nist.gov/vuln/detail/CVE-2021-3712
security-tracker.debian.org/tracker/CVE-2021-3712
ubuntu.com/security/notices/USN-5051-1
ubuntu.com/security/notices/USN-5051-2
ubuntu.com/security/notices/USN-5051-3
ubuntu.com/security/notices/USN-5051-4 (regression only in trusty/esm)
ubuntu.com/security/notices/USN-5088-1
www.cve.org/CVERecord?id=CVE-2021-3712
www.openssl.org/news/secadv/20210824.txt
7.4 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:H
5.8 Medium
CVSS2
Access Vector
NETWORK
Access Complexity
MEDIUM
Authentication
NONE
Confidentiality Impact
PARTIAL
Integrity Impact
NONE
Availability Impact
PARTIAL
AV:N/AC:M/Au:N/C:P/I:N/A:P
0.005 Low
EPSS
Percentile
75.6%