BturnerATLASSIAN:BSERV-13093Upgrade Logback for CVE-2021-42550
6.6 Medium
CVSS3
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
HIGH
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H
8.5 High
CVSS2
Access Vector
NETWORK
Access Complexity
MEDIUM
Authentication
SINGLE
Confidentiality Impact
COMPLETE
Integrity Impact
COMPLETE
Availability Impact
COMPLETE
AV:N/AC:M/Au:S/C:C/I:C/A:C
h3. Issue Summary
In the wake of Log4Shell, CVE-2021-42550 has been created for similar JNDI considerations in Logback. The Logback maintainers have removed some functionality from Logback in response and released Logback 1.2.9.
Please note: There is no RCE in Logback, and there is no vulnerability in Bitbucket Server or Logback’s default configurations. There is also no mechanism whereby a malicious client can attack the system. Exercising CVE-2021-42550 requires write access to Bitbucket Server’s Logback configuration.
h3. Workaround
Manually audit logging configuration and ensure proper permissions.
| CPE | Name | Operator | Version |
|---|---|---|---|
| bitbucket server | le | 6.10.0 | |
| bitbucket server | lt | 7.19.2 | |
| bitbucket server | lt | 7.17.5 | |
| bitbucket server | lt | 6.10.17 | |
| bitbucket server | lt | 7.20.0 | |
| bitbucket server | lt | 7.6.13 |
Related
6.6 Medium
CVSS3
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
HIGH
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H
8.5 High
CVSS2
Access Vector
NETWORK
Access Complexity
MEDIUM
Authentication
SINGLE
Confidentiality Impact
COMPLETE
Integrity Impact
COMPLETE
Availability Impact
COMPLETE
AV:N/AC:M/Au:S/C:C/I:C/A:C