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CVE-2020-1967

Segmentation fault in SSL_check_chain

Published: Apr 21, 2020Updated: Nov 21, 2024 Sources: CVE List NVD GHSA BDU csafCWE-476
NVD MITRE
7.5CVSSHIGH
EPSS Score
53.3%
Top 1.2%
CISA KEV
Not in KEV
Exploits
3 Known
Remediation
Patch Available

Description

Server or client applications that call the SSL_check_chain() function during or after a TLS 1.3 handshake may crash due to a NULL pointer dereference as a result of incorrect handling of the "signature_algorithms_cert" TLS extension. The crash occurs if an invalid or unrecognised signature algorithm is received from the peer. This could be exploited by a malicious peer in a Denial of Service attack. OpenSSL version 1.1.1d, 1.1.1e, and 1.1.1f are affected by this issue. This issue did not affect OpenSSL versions prior to 1.1.1d. Fixed in OpenSSL 1.1.1g (Affected 1.1.1d-1.1.1f).

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:NI:NA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:NIntegrity
None
A:HAvailability
High
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Weaknesses

CWE-476

Affected Products

OpenSSLOpenSSLOSS Libraries
Debian GNU/LinuxСообщество свободного программного обеспечения
On-premOS
Operating Systems / linux-distro
Astra Linux Special EditionООО «РусБИТех-Астра»
On-premOS
Operating Systems / linux-distro
Astra Linux Common EditionООО «РусБИТех-Астра»
On-premOS
Operating Systems / linux-distro
OpenSUSE LeapNovell Inc.
On-premOS
Operating Systems / linux-distro
openssloss-projectUSOSS Librariesaka open ssl
сообщество свободного программного обеспеченияoss-projectOperating Systemsaka сообщество свободного программного обеспечения, fsf
ооо «русбитех-астра»commercialRUOperating Systemsaka rusbitech-astra
novell inc.commercialUSOperating Systems
and 37 more affected products View all →

Attack Graph

Products CVE Techniques Tactics

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Exploitability

3 exploit sources identified

Exploit details including PoC links, Metasploit modules, and scanner templates are available after registration.

View exploit details
Official Patch Available

MITRE ATT&CK

2 techniques
Impact
Initial Access
View detailed technique mapping

References

https://security.FreeBSD.org/advisories/FreeBSD-SA-20:11.openssl.asc
security.freebsd.org
https://www.debian.org/security/2020/dsa-4661
debian.org
http://www.openwall.com/lists/oss-security/2020/04/22/2
openwall.com
and 73 more references View all →

Timeline

Published
Apr 21, 2020
Last Updated
Nov 21, 2024

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