7.5 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
7.8 High
AI Score
Confidence
High
0.001 Low
EPSS
Percentile
47.0%
The function PEM_read_bio_ex() reads a PEM file from a BIO and parses and
decodes the βnameβ (e.g. βCERTIFICATEβ), any header data and the payload data.
If the function succeeds then the βname_outβ, βheaderβ and βdataβ arguments are
populated with pointers to buffers containing the relevant decoded data. The
caller is responsible for freeing those buffers. It is possible to construct a
PEM file that results in 0 bytes of payload data. In this case PEM_read_bio_ex()
will return a failure code but will populate the header argument with a pointer
to a buffer that has already been freed. If the caller also frees this buffer
then a double free will occur. This will most likely lead to a crash. This
could be exploited by an attacker who has the ability to supply malicious PEM
files for parsing to achieve a denial of service attack.
The functions PEM_read_bio() and PEM_read() are simple wrappers around
PEM_read_bio_ex() and therefore these functions are also directly affected.
These functions are also called indirectly by a number of other OpenSSL
functions including PEM_X509_INFO_read_bio_ex() and
SSL_CTX_use_serverinfo_file() which are also vulnerable. Some OpenSSL internal
uses of these functions are not vulnerable because the caller does not free the
header argument if PEM_read_bio_ex() returns a failure code. These locations
include the PEM_read_bio_TYPE() functions as well as the decoders introduced in
OpenSSL 3.0.
The OpenSSL asn1parse command line application is also impacted by this issue.
CPE | Name | Operator | Version |
---|---|---|---|
openssl:openssl | openssl | lt | 1.1.1t |
openssl:openssl | openssl | lt | 3.0.8 |
[
{
"defaultStatus": "unaffected",
"product": "OpenSSL",
"vendor": "OpenSSL",
"versions": [
{
"lessThan": "3.0.8",
"status": "affected",
"version": "3.0.0",
"versionType": "semver"
},
{
"lessThan": "1.1.1t",
"status": "affected",
"version": "1.1.1",
"versionType": "custom"
}
]
}
]
7.5 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
7.8 High
AI Score
Confidence
High
0.001 Low
EPSS
Percentile
47.0%