Multiple vulnerabilities in OpenSSL



| Updated: 2022-06-03
Risk Medium
Patch available YES
Number of vulnerabilities 3
CVE-ID CVE-2021-23841
CVE-2021-23839
CVE-2021-23840
CWE-ID CWE-476
CWE-310
CWE-20
Exploitation vector Network
Public exploit N/A
Vulnerable software
 OpenSSL
Server applications / Encryption software

Vendor OpenSSL Software Foundation

Security Bulletin

This security bulletin contains information about 3 vulnerabilities.

1) NULL pointer dereference

EUVDB-ID: #VU50740

Risk: Medium

CVSSv4.0: 4.6 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-23841

CWE-ID: CWE-476 - NULL Pointer Dereference

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to a NULL pointer dereference error within the X509_issuer_and_serial_hash() function when parsing the issuer field in the X509 certificate. A remote attacker can supply a specially crafted certificate, trigger a NULL pointer dereference error and perform a denial of service (DoS) attack.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

OpenSSL: 1.0.0o - 1.1.1

CPE2.3 External links

https://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=6a51b9e1d0cf0bf8515f7201b68fb0a3482b3dc1
https://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=9b1129239f3ebb1d1c98ce9ed41d5c9476c47cb2
https://www.openssl.org/news/secadv/20210216.txt


Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

2) Cryptographic issues

EUVDB-ID: #VU50744

Risk: Low

CVSSv4.0: 1.7 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-23839

CWE-ID: CWE-310 - Cryptographic Issues

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform a MitM attack.

The vulnerability exists due to a faulty implementation of the padding check when server is configured to support SSLv2 protocol. A remote attacker can perform a MitM attack and force the server to use less secure protocols.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

OpenSSL: 1.0.2x - 1.0.2s

CPE2.3 External links

https://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=30919ab80a478f2d81f2e9acdcca3fa4740cd547
https://www.openssl.org/news/secadv/20210216.txt
https://www.trustwave.com/en-us/resources/security-resources/security-advisories/?fid=28459


Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

3) Input validation error

EUVDB-ID: #VU50745

Risk: Medium

CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-23840

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to insufficient validation of user-supplied input during EVP_CipherUpdate, EVP_EncryptUpdate and EVP_DecryptUpdate calls. A remote attacker can pass specially crafted input to the application and perform a denial of service (DoS) attack.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

OpenSSL: 1.0.0o - 1.1.1

CPE2.3 External links

https://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=6a51b9e1d0cf0bf8515f7201b68fb0a3482b3dc1
https://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=9b1129239f3ebb1d1c98ce9ed41d5c9476c47cb2
https://www.openssl.org/news/secadv/20210216.txt


Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.



###SIDEBAR###