Gentoo update for OpenSSL

Published: 2021-03-31 | Updated: 2022-06-03

Risk	Medium
Patch available	YES
Number of vulnerabilities	4
CVE-ID	CVE-2021-23840 CVE-2021-23841 CVE-2021-3449 CVE-2021-3450
CWE-ID	CWE-20 CWE-476 CWE-254
Exploitation vector	Network
Public exploit	Public exploit code for vulnerability #3 is available.
Vulnerable software Subscribe	Gentoo Linux Operating systems & Components / Operating system
Vendor	Gentoo

Security Bulletin

This security bulletin contains information about 4 vulnerabilities.

1) Input validation error

EUVDB-ID: #VU50745

Risk: Medium

CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

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

Update the affected packages.
dev-libs/openssl to version: 1.1.1k

Vulnerable software versions

Gentoo Linux: All versions

External links

http://security.gentoo.org/
http://security.gentoo.org/glsa/202103-03

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) NULL pointer dereference

EUVDB-ID: #VU50740

Risk: Medium

CVSSv3.1: 5.2 [CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

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

Update the affected packages.
dev-libs/openssl to version: 1.1.1k

Vulnerable software versions

Gentoo Linux: All versions

External links

http://security.gentoo.org/
http://security.gentoo.org/glsa/202103-03

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) NULL pointer dereference

EUVDB-ID: #VU51733

Risk: Medium

CVSSv3.1: 6.7 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P/RL:O/RC:C]

CVE-ID: CVE-2021-3449

CWE-ID: CWE-476 - NULL Pointer Dereference

Exploit availability: Yes

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 when processing TLSv1.2 renegotiations. A remote attacker can send a maliciously crafted renegotiation ClientHello message, which omits the signature_algorithms extension but includes a signature_algorithms_cert extension, trigger a NULL pointer dereference error and crash the server.

Mitigation

Update the affected packages.
dev-libs/openssl to version: 1.1.1k

Vulnerable software versions

Gentoo Linux: All versions

External links

http://security.gentoo.org/
http://security.gentoo.org/glsa/202103-03

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. However, proof of concept for this vulnerability is available.

4) Security features bypass

EUVDB-ID: #VU51732

Risk: Medium

CVSSv3.1: 5.7 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-3450

CWE-ID: CWE-254 - Security Features

Exploit availability: No

Description

The vulnerability allows a remote attacker to bypass implemented security restrictions.

The vulnerability exists due to an error in implementation of the X509_V_FLAG_X509_STRICT flag allows an attacker to overwrite a valid CA certificate using any non-CA certificate in the chain. As a result, a remote attacker can perform MitM attack.

Mitigation

Update the affected packages.
dev-libs/openssl to version: 1.1.1k

Vulnerable software versions

Gentoo Linux: All versions

External links

http://security.gentoo.org/
http://security.gentoo.org/glsa/202103-03

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.