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CVE-2021-3450Suited to automated attack · CISA

CA certificate check bypass with X509_V_FLAG_X509_STRICT

CVSS score

7.4

EPSS probability

%18.3

Risk score

1.4

Published

5 y ago

OverviewPublic Exploits (0)NewsroomVulnerability Timeline
Official patch verified

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Vulnerability description

DayBreach CVE AI Research

CVE-2021-3450 has vendor, distribution, patch and security-source records on file. We can compare them and prepare an explanation linked to the evidence.

The X509_V_FLAG_X509_STRICT flag enables additional security checks of the certificates present in a certificate chain. It is not set by default. Starting from OpenSSL version 1.1.1h a check to disallow certificates in the chain that have explicitly encoded elliptic curve parameters was added as an additional strict check. An error in the implementation of this check meant that the result of a previous check to confirm that certificates in the chain are valid CA certificates was overwritten. This effectively bypasses the check that non-CA certificates must not be able to issue other certificates. If a "purpose" has been configured then there is a subsequent opportunity for checks that the certificate is a valid CA. All of the named "purpose" values implemented in libcrypto perform this check. Therefore, where a purpose is set the certificate chain will still be rejected even when the strict flag has been used. A purpose is set by default in libssl client and server certificate verification routines, but it can be overridden or removed by an application. In order to be affected, an application must explicitly set the X509_V_FLAG_X509_STRICT verification flag and either not set a purpose for the certificate verification or, in the case of TLS client or server applications, override the default purpose. OpenSSL versions 1.1.1h and newer 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 1.1.1h-1.1.1j).

IMPACT: Affected Products and Software

Affected Products

The following products are affected by CVE-2021-3450 vulnerability. Where our threat engine knows the exact affected versions, they are listed below.

IDVENDORPRODUCTACTION
1opensslopenssl View
2opensslopenssl View
3freebsdfreebsd View
4netappsantricity smi-s provider firmware View
5netappsantricity smi-s provider View
6netappstoragegrid firmware View
7netappstoragegrid View
8windriverlinux View
9windriverlinux View
10windriverlinux View
11windriverlinux View
12netappcloud volumes ontap mediator View
13netapponcommand workflow automation View
14netappontap select deploy administration utility View
15fedoraprojectfedora View
16tenablenessus View
17tenablenessus agent View
18tenablenessus network monitor View
19tenablenessus network monitor View
20tenablenessus network monitor View
21tenablenessus network monitor View
22tenablenessus network monitor View
23oraclecommerce guided search View
24oracleenterprise manager for storage management View
25oraclegraalvm View
26oraclegraalvm View
27oraclegraalvm View
28oraclejd edwards enterpriseone tools View
29oraclejd edwards world security View
30oraclemysql connectors View
31oraclemysql enterprise monitor View
32oraclemysql server View
33oraclemysql server View
34oraclemysql workbench View
35oraclepeoplesoft enterprise peopletools View
36oraclesecure backup View
37oraclesecure global desktop View
38oracleweblogic server View
39oracleweblogic server View
40mcafeeweb gateway View
41mcafeeweb gateway View
42mcafeeweb gateway View
43mcafeeweb gateway cloud service View
44mcafeeweb gateway cloud service View
45mcafeeweb gateway cloud service View
46sonicwallsma100 firmware View
47sonicwallSMA100 View
48sonicwallcapture client View
49sonicwallemail security View
50sonicwallSonicOS View
51nodejsnode.js View
52nodejsnode.js View
53nodejsnode.js View
54nodejsnode.js View
Total affected vendors: 10|Products: 54

RED HAT CSAF/VEX: Product Impact Check

Red Hat has not yet published a CSAF/VEX impact record for this CVE. This does not mean “not affected”.

SCORING: CVSS from Multiple Sources

CVSS Scores

The Common Vulnerability Scoring System is a standardised framework for assessing the severity of vulnerabilities in software and systems. We collect and display CVSS scores from several sources for each CVE.

SCOREVERSIONSEVERITYVECTORSOURCE
7.4CVSS V31HIGHCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:NNVD
5.8CVSS V2—AV:N/AC:M/Au:N/C:P/I:P/A:NNVD

Patch and Remediation Guide

Solution & Remediation Advisory

Patch verified

5 doğrulanmış yama veya düzeltilmiş sürüm kanıtı bulundu.

nvd

NVD tarafından Patch olarak etiketlenmiş referans

Open source
nvd

NVD tarafından Patch olarak etiketlenmiş referans

Open source
nvd

NVD tarafından Patch olarak etiketlenmiş referans

Open source
nvd

NVD tarafından Patch olarak etiketlenmiş referans

Open source
nvd

NVD tarafından Patch olarak etiketlenmiş referans

Open source
Confirm the affected product and version against the source evidence above.
Restrict access to internet-facing services and apply network segmentation.
Apply the official update named in the evidence only to the matching product and version.
Monitor server logs and network endpoints for signs of anomalous execution.

Public exploit and active exploitation status

Verified exploit intelligence

No verified public PoC, exploit repository or Metasploit module has been found for this CVE yet.

Weakness Classification and Attack Patterns (CWE & CAPEC)

CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorises the common flaws or weaknesses that can lead to vulnerabilities. CVE-2021-3450 is associated with the following CWEs:

CWE-295: Common Weakness Enumeration Entry CWE-295

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2021-3450 weaknesses.

CAPEC-66: SQL InjectionCAPEC-126: Path TraversalCAPEC-28: OS Command Injection

Attack Vector and Accessibility

ExposureAğ üzerinden
PermissionsGerekmiyor
UserGerekmiyor

Official Sources and Advisories

https://www.openssl.org/news/secadv/20210325.txtvendor-advisoryhttps://git.openssl.org/gitweb/?p=openssl.git%3Ba=commitdiff%3Bh=2a40b7bc7b94dd7de897a74571e7024f0cf0d63bvendor-advisory20210325 Multiple Vulnerabilities in OpenSSL Affecting Cisco Products: March 2021vendor-advisory[oss-security] 20210327 OpenSSL 1.1.1 CVE-2021-3450 CA certificate check bypass with X509_V_FLAG_X509_STRICT, CVE-2021-3449 NULL pointer deref in signature_algorithms processingvendor-advisory[oss-security] 20210327 Re: OpenSSL 1.1.1 CVE-2021-3450 CA certificate check bypass with X509_V_FLAG_X509_STRICT, CVE-2021-3449 NULL pointer deref in signature_algorithms processingvendor-advisory[oss-security] 20210328 Re: OpenSSL 1.1.1 CVE-2021-3450 CA certificate check bypass with X509_V_FLAG_X509_STRICT, CVE-2021-3449 NULL pointer deref in signature_algorithms processingvendor-advisory[oss-security] 20210328 Re: OpenSSL 1.1.1 CVE-2021-3450 CA certificate check bypass with X509_V_FLAG_X509_STRICT, CVE-2021-3449 NULL pointer deref in signature_algorithms processingvendor-advisoryGLSA-202103-03vendor-advisoryFEDORA-2021-cbf14ab8f9vendor-advisoryhttps://www.oracle.com/security-alerts/cpuApr2021.htmlvendor-advisory

CVSS Vector Radar Chart

7.4 / 10
Attack VectorNetworkComplexityHighPrivilegesNoneUser Interact.NoneConfidentialityHighIntegrityNoneAvailabilityNone

Vulnerability Scoring Details

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
Attack VectorNetwork
Attack ComplexityHigh
Privileges RequiredNone required
User InteractionNone required
Confidentiality (Gizlilik)High
Integrity (Bütünlük)None
Availability (Erişilebilirlik)None

Yama doğrulandı

5 doğrulanmış yama veya düzeltilmiş sürüm kanıtı bulundu.

Follow the vendor

O
openssl logo
openssl
F
freebsd logo
freebsd
N
netapp logo
netapp
W
windriver logo
windriver
F
fedoraproject logo
fedoraproject
T
tenable logo
tenable

Weakness Type (CWE & CAPEC)

CWE-295

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CVE-2021-3450 · CA certificate check bypass with X509_V_FLAG_X509_STRICT · DayBreach