CVE-2021-3449

medium

Description

An OpenSSL TLS server may crash if sent a maliciously crafted renegotiation ClientHello message from a client. If a TLSv1.2 renegotiation ClientHello omits the signature_algorithms extension (where it was present in the initial ClientHello), but includes a signature_algorithms_cert extension then a NULL pointer dereference will result, leading to a crash and a denial of service attack. A server is only vulnerable if it has TLSv1.2 and renegotiation enabled (which is the default configuration). OpenSSL TLS clients are not impacted by this issue. All OpenSSL 1.1.1 versions are affected by this issue. Users of these versions should upgrade to OpenSSL 1.1.1k. OpenSSL 1.0.2 is not impacted by this issue. Fixed in OpenSSL 1.1.1k (Affected 1.1.1-1.1.1j).

References

https://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=fb9fa6b51defd48157eeb207f52181f735d96148

https://www.openssl.org/news/secadv/20210325.txt

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-openssl-2021-GHY28dJd

https://www.debian.org/security/2021/dsa-4875

https://security.netapp.com/advisory/ntap-20210326-0006/

https://security.FreeBSD.org/advisories/FreeBSD-SA-21:07.openssl.asc

http://www.openwall.com/lists/oss-security/2021/03/27/1

http://www.openwall.com/lists/oss-security/2021/03/27/2

http://www.openwall.com/lists/oss-security/2021/03/28/3

http://www.openwall.com/lists/oss-security/2021/03/28/4

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

https://www.tenable.com/security/tns-2021-06

https://www.tenable.com/security/tns-2021-05

https://lists.fedoraproject.org/archives/list/[email protected]/message/CCBFLLVQVILIVGZMBJL3IXZGKWQISYNP/

https://kc.mcafee.com/corporate/index?page=content&id=SB10356

https://www.tenable.com/security/tns-2021-09

https://security.netapp.com/advisory/ntap-20210513-0002/

https://www.tenable.com/security/tns-2021-10

https://www.oracle.com/security-alerts/cpuApr2021.html

https://cert-portal.siemens.com/productcert/pdf/ssa-772220.pdf

https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA44845

https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0013

https://www.oracle.com//security-alerts/cpujul2021.html

https://lists.debian.org/debian-lts-announce/2021/08/msg00029.html

https://www.oracle.com/security-alerts/cpuoct2021.html

https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf

https://www.oracle.com/security-alerts/cpuapr2022.html

https://www.oracle.com/security-alerts/cpujul2022.html

Details

Source: MITRE

Published: 2021-03-25

Updated: 2022-07-25

Type: CWE-476

Risk Information

CVSS v2

Base Score: 4.3

Vector: AV:N/AC:M/Au:N/C:N/I:N/A:P

Impact Score: 2.9

Exploitability Score: 8.6

Severity: MEDIUM

CVSS v3

Base Score: 5.9

Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Impact Score: 3.6

Exploitability Score: 2.2

Severity: MEDIUM