Spring-boot-admin sandbox bypass via crafted HTML

Description

Thymeleaf through 3.1.1.RELEASE as used in spring-boot-admin (aka Spring Boot Admin) through 3.1.1 allows for a sandbox bypass via crafted HTML. This may be relevant for SSTI (Server Side Template Injection) and code execution in spring-boot-admin if MailNotifier is enabled and there is write access to environment variables via the UI.

Spring Boot Admin 3.1.2 and 2.7.16 contain mitigations for the issue. This bypass is achived via a library called Thymeleaf which has added counter measures for this sort of bypass in version 3.1.2.RELEASE which has explicity forbidden static access to org.springframework.util in expressions. Thymeleaf itself should not be considered vulnerable.

Basic information

Type
reviewed
Severity
high
Advisory on GitHub
Open advisory ↗
Repository advisory
Source code
Browse source ↗
Published (advisory)
2023-07-14 06:31:00 UTC
Updated
2024-06-12 22:40:52 UTC
GitHub reviewed
2023-07-14 21:50:50 UTC
NVD published
2023-07-14

EPSS Score

Score Percentile
0.14% 34.89%

CVSS Scores

Base score Version Severity Vector
7.5 3.1
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.

Identifiers

CWEs

CWE id Name
CWE-77 Improper Neutralization of Special Elements used in a Command ('Command Injection')

Credits

  • ymuraki-csc (analyst)
  • danielfernandez (analyst)
  • Subrhamanya (analyst)

Affected packages (2)

Vulnerable version ranges and first patched releases as published by GitHub.

Ecosystem Package Vulnerable range First patched Vulnerable functions
maven de.codecentric:spring-boot-admin-server >= 3.0.0, < 3.1.2 3.1.2
maven de.codecentric:spring-boot-admin-server < 2.7.16 2.7.16

References

cvelogic Threat Intelligence