Red Hat Enterprise Linux 8 update for libyang
| Risk | High |
| Patch available | YES |
| Number of vulnerabilities | 8 |
| CVE-ID | CVE-2019-20398 CVE-2019-20396 CVE-2019-20393 CVE-2019-20395 CVE-2019-20394 CVE-2019-20392 CVE-2019-20397 CVE-2019-20391 |
| CWE-ID | CWE-476 CWE-20 CWE-415 CWE-400 CWE-119 |
| Exploitation vector | Network |
| Public exploit | N/A |
| Vulnerable software |
Red Hat Enterprise Linux for x86_64 Operating systems & Components / Operating system libyang (Red Hat package) Operating systems & Components / Operating system package or component |
| Vendor | Red Hat Inc. |
Security Bulletin
This security bulletin contains information about 8 vulnerabilities.
1) NULL pointer dereference
EUVDB-ID: #VU34868
Risk: Medium
CVSSv4.0: 4.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]
CVE-ID: CVE-2019-20398
CWE-ID:
CWE-476 - NULL Pointer Dereference
Exploit availability: No
DescriptionThe vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to a NULL pointer dereference error in libyang before v1.0-r3 in the function lys_extension_instances_free() due to a copy of unresolved extensions in lys_restr_dup(). Applications that use libyang to parse untrusted input yang files may crash. A remote attacker can perform a denial of service (DoS) attack.
MitigationInstall update from vendor's website.
Vulnerable software versionsRed Hat Enterprise Linux for x86_64: 8.0
libyang (Red Hat package): before 1.0.184-1.el8
CPE2.3- cpe:2.3:o:red_hat:red_hat_enterprise_linux:8.0:*:*:*:*:*:*:*
- cpe:2.3:a:red_hat:libyang_redhat_package:*:*:*:*:*:red_hat_enterprise_linux:*:*
https://access.redhat.com/errata/RHEA-2021:1906
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) Input validation error
EUVDB-ID: #VU34866
Risk: Medium
CVSSv4.0: 4.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]
CVE-ID: CVE-2019-20396
CWE-ID:
CWE-20 - Improper input validation
Exploit availability: No
DescriptionThe vulnerability allows a remote non-authenticated attacker to perform a denial of service (DoS) attack.
A segmentation fault is present in yyparse in libyang before v1.0-r1 due to a malformed pattern statement value during lys_parse_path parsing.
MitigationInstall update from vendor's website.
Vulnerable software versionsRed Hat Enterprise Linux for x86_64: 8.0
libyang (Red Hat package): before 1.0.184-1.el8
CPE2.3- cpe:2.3:o:red_hat:red_hat_enterprise_linux:8.0:*:*:*:*:*:*:*
- cpe:2.3:a:red_hat:libyang_redhat_package:*:*:*:*:*:red_hat_enterprise_linux:*:*
https://access.redhat.com/errata/RHEA-2021:1906
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) Double Free
EUVDB-ID: #VU34863
Risk: High
CVSSv4.0: 6.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]
CVE-ID: CVE-2019-20393
CWE-ID:
CWE-415 - Double Free
Exploit availability: No
DescriptionThe vulnerability allows a remote non-authenticated attacker to execute arbitrary code.
A double-free is present in libyang before v1.0-r1 in the function yyparse() when an empty description is used. Applications that use libyang to parse untrusted input yang files may be vulnerable to this flaw, which would cause a crash or potentially code execution.
MitigationInstall update from vendor's website.
Vulnerable software versionsRed Hat Enterprise Linux for x86_64: 8.0
libyang (Red Hat package): before 1.0.184-1.el8
CPE2.3- cpe:2.3:o:red_hat:red_hat_enterprise_linux:8.0:*:*:*:*:*:*:*
- cpe:2.3:a:red_hat:libyang_redhat_package:*:*:*:*:*:red_hat_enterprise_linux:*:*
https://access.redhat.com/errata/RHEA-2021:1906
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.
4) Resource exhaustion
EUVDB-ID: #VU34865
Risk: Medium
CVSSv4.0: 4.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]
CVE-ID: CVE-2019-20395
CWE-ID:
CWE-400 - Resource exhaustion
Exploit availability: No
DescriptionThe vulnerability allows a remote non-authenticated attacker to perform a denial of service (DoS) attack.
A stack consumption issue is present in libyang before v1.0-r1 due to the self-referential union type containing leafrefs. Applications that use libyang to parse untrusted input yang files may crash.
MitigationInstall update from vendor's website.
Vulnerable software versionsRed Hat Enterprise Linux for x86_64: 8.0
libyang (Red Hat package): before 1.0.184-1.el8
CPE2.3- cpe:2.3:o:red_hat:red_hat_enterprise_linux:8.0:*:*:*:*:*:*:*
- cpe:2.3:a:red_hat:libyang_redhat_package:*:*:*:*:*:red_hat_enterprise_linux:*:*
https://access.redhat.com/errata/RHEA-2021:1906
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.
5) Double Free
EUVDB-ID: #VU34864
Risk: High
CVSSv4.0: 6.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]
CVE-ID: CVE-2019-20394
CWE-ID:
CWE-415 - Double Free
Exploit availability: No
DescriptionThe vulnerability allows a remote non-authenticated attacker to execute arbitrary code.
A double-free is present in libyang before v1.0-r3 in the function yyparse() when a type statement in used in a notification statement. Applications that use libyang to parse untrusted input yang files may be vulnerable to this flaw, which would cause a crash or potentially code execution.
MitigationInstall update from vendor's website.
Vulnerable software versionsRed Hat Enterprise Linux for x86_64: 8.0
libyang (Red Hat package): before 1.0.184-1.el8
CPE2.3- cpe:2.3:o:red_hat:red_hat_enterprise_linux:8.0:*:*:*:*:*:*:*
- cpe:2.3:a:red_hat:libyang_redhat_package:*:*:*:*:*:red_hat_enterprise_linux:*:*
https://access.redhat.com/errata/RHEA-2021:1906
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.
6) Buffer overflow
EUVDB-ID: #VU34862
Risk: Medium
CVSSv4.0: 4.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]
CVE-ID: CVE-2019-20392
CWE-ID:
CWE-119 - Memory corruption
Exploit availability: No
DescriptionThe vulnerability allows a remote non-authenticated attacker to perform a denial of service (DoS) attack.
An invalid memory access flaw is present in libyang before v1.0-r1 in the function resolve_feature_value() when an if-feature statement is used inside a list key node, and the feature used is not defined. Applications that use libyang to parse untrusted input yang files may crash.
MitigationInstall update from vendor's website.
Vulnerable software versionsRed Hat Enterprise Linux for x86_64: 8.0
libyang (Red Hat package): before 1.0.184-1.el8
CPE2.3- cpe:2.3:o:red_hat:red_hat_enterprise_linux:8.0:*:*:*:*:*:*:*
- cpe:2.3:a:red_hat:libyang_redhat_package:*:*:*:*:*:red_hat_enterprise_linux:*:*
https://access.redhat.com/errata/RHEA-2021:1906
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.
7) Double Free
EUVDB-ID: #VU34867
Risk: High
CVSSv4.0: 6.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]
CVE-ID: CVE-2019-20397
CWE-ID:
CWE-415 - Double Free
Exploit availability: No
DescriptionThe vulnerability allows a remote non-authenticated attacker to execute arbitrary code.
A double-free is present in libyang before v1.0-r1 in the function yyparse() when an organization field is not terminated. Applications that use libyang to parse untrusted input yang files may be vulnerable to this flaw, which would cause a crash or potentially code execution.
MitigationInstall update from vendor's website.
Vulnerable software versionsRed Hat Enterprise Linux for x86_64: 8.0
libyang (Red Hat package): before 1.0.184-1.el8
CPE2.3- cpe:2.3:o:red_hat:red_hat_enterprise_linux:8.0:*:*:*:*:*:*:*
- cpe:2.3:a:red_hat:libyang_redhat_package:*:*:*:*:*:red_hat_enterprise_linux:*:*
https://access.redhat.com/errata/RHEA-2021:1906
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.
8) Buffer overflow
EUVDB-ID: #VU34861
Risk: Medium
CVSSv4.0: 4.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]
CVE-ID: CVE-2019-20391
CWE-ID:
CWE-119 - Memory corruption
Exploit availability: No
DescriptionThe vulnerability allows a remote non-authenticated attacker to perform a denial of service (DoS) attack.
An invalid memory access flaw is present in libyang before v1.0-r3 in the function resolve_feature_value() when an if-feature statement is used inside a bit. Applications that use libyang to parse untrusted input yang files may crash.
MitigationInstall update from vendor's website.
Vulnerable software versionsRed Hat Enterprise Linux for x86_64: 8.0
libyang (Red Hat package): before 1.0.184-1.el8
CPE2.3- cpe:2.3:o:red_hat:red_hat_enterprise_linux:8.0:*:*:*:*:*:*:*
- cpe:2.3:a:red_hat:libyang_redhat_package:*:*:*:*:*:red_hat_enterprise_linux:*:*
https://access.redhat.com/errata/RHEA-2021:1906
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.
