Improperly implemented security check for standard in firefox (Alpine package)
| Risk | Medium |
| Patch available | YES |
| Number of vulnerabilities | 1 |
| CVE-ID | CVE-2020-26961 |
| CWE-ID | CWE-358 |
| Exploitation vector | Network |
| Public exploit | N/A |
| Vulnerable software Subscribe |
firefox (Alpine package) Operating systems & Components / Operating system package or component |
| Vendor | Alpine Linux Development Team |
Security Bulletin
This security bulletin contains one medium risk vulnerability.
1) Improperly implemented security check for standard
EUVDB-ID: #VU48466
Risk: Medium
CVSSv3.1: 4.7 [CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N/E:U/RL:O/RC:C]
CVE-ID: CVE-2020-26961
CWE-ID:
CWE-358 - Improperly Implemented Security Check for Standard
Exploit availability: No
DescriptionThe vulnerability allows a remote attacker to perform a DNS rebinding attack.
The vulnerability exists due to the way Firefox filters IPv4 mapped IP addresses. When DNS over HTTPS is in use, it intentionally filters RFC1918 and related IP ranges from the responses as these do not make sense coming from a DoH resolver. However when an IPv4 address was mapped through IPv6, these addresses were erroneously let through, leading to a potential DNS Rebinding attack.
MitigationInstall update from vendor's website.
Vulnerable software versionsfirefox (Alpine package): 77.0-r0 - 79.0-r1
External linkshttp://git.alpinelinux.org/aports/commit/?id=13a8f0d1284680f721e935cc6d3cb2649cf25093
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.
