Thinking...
The user wants me to analyze a bug bounty report about an ACL cache collisi
collision vulnerability in MariaDB and convert it into a reusable, target-a
target-agnostic test case template.
Let me first understand the vulnerability:
- The vulnerability is about a cache key collision between role lookups an
and UNIX socket users
- When both share the same name and (IP/host, user, db) combination, they
collide
- This allows privilege escalation through caching of another user's datab
database privileges
- It affects MariaDB specifically - it's a database management system vuln
vulnerability
Key details from the report:
- Type: Cache collision / Privilege confusion
- Category: This is database specific - I'll categorize as "Web App" or "Ot
"Other" since it could be part of a web application using MariaDB, but the
core issue is in the database itself. Actually, looking at the categories a
available (Web App, API, Network, Mobile App, Desktop App, Library, Blockch
Blockchain, Source Code, Other), I think "Other" makes sense since it's fun
fundamentally a database security issue.
- Attack: Creating same-named role and user over socket/remote connection,
exploiting cache collision
Now I need to determine if this is reusable:
This is actually quite specific to MariaDB as a database system with specif
specific caching mechanisms. However, the concept of "cache collision leadi
leading to privilege confusion" could theoretically apply to other database
database systems or even authorization frameworks in general. The attack re
requires understanding that both roles and socket users can share cache key
keys based on (IP, user, db) tuples.
This is somewhat specific but could be generalized as a test case for:
- "Privilege Confusion via Cache Collision" - testing whether privilege ch
checking properly distinguishes between different principals
The vulnerability depends heavily on MariaDB's specific caching architectur
architecture which may not exist identically in all databases. However, the
the core concept of cache collisions leading to unauthorized access is tran
transferable to any system that:
- Uses cached privilege lookups
- Has similar naming conflicts between roles and users
- Doesn't properly distinguish between different authorization contexts
I'll create a generic test case focusing on "Privilege Confusion via Cache
Collision" and use placeholders like <TARGET_SYSTEM> to represent the speci
specific database or system being tested. The core steps would be: setting
up same-named role and user, warming the cache with privileged user access,
access, then attempting to activate the role from a different context.
Actually, I need to reconsider - this is very specific to MariaDB's interna
internal caching implementation. The exact mechanism involves (IP, user, db
db) tuples matching between socket users and remote roles, which would requ
require knowledge of that particular system's internals to replicate on any
any other database or system. For general security testing purposes, the pr
principle could apply but I need enough detail from the report to make it u
usable without knowing MariaDB-specific implementation details.
Looking at what the report actually describes: cache key generation using (
(ip, user, db), role activation through privilege lookup, and how both sock
socket users and roles can collide when they share identical names within t
that same namespace. While this is a very specific bug tied to MariaDB's ar
architecture, I can still abstract it into testable steps that don't refere
reference the specific database product name - focusing instead on what the
the attacker actually does: creating similar-named entities, establishing c
cache access patterns, and attempting privilege elevation through the colli
collision mechanism.
I'll structure this with clear, target-agnostic steps using placeholders wh
where needed, keeping the core vulnerability concept intact without anchori
anchoring it to MariaDB's internal workings.
...done thinking.
Description: This issue allows a role holder to inherit database privil
privileges from another user account through cache key collision. When diff
different principals (roles or socket users) share the same name and system
system identifiers, they may retrieve cached results meant for different au
authorization contexts, bypassing intended access controls.
How to Test:
- As administrator, create a new test role with the same name as an existi
existing user account that has overprivileged database permissions: `CREATE
CREATE ROLE <ROLE_NAME>;
- Ensure the same-named user already exists in the system and has elevated
elevated privileges on at least one resource: <RESOURCE_NAME>;;
- Grant the same-named role to a limited-access account that should only h
have minimal privileges: GRANT <ROLE_NAME> TO '<LIMITED_USER>'@'<HOST>';;
'<LIMITED_USER>'@'<HOST>';`;
- Connect using the privileged socket user or
connection first and perform an action to populate the privilege cache: `SE
SELECT marker FROM <RESOURCE_TABLE>;;
- Disconnect and reconnect as the limited-access account;
- Activate the role from this new connection and attempt to access a resou
resource that should be restricted: `SET ROLE <ROLE_NAME>; SELECT marker FR
FROM <RESOURCE_TABLE>;`;
Impact: A low-privilege role holder can access data or perform operatio
operations outside their authorized scope due to cache-based privilege conf
confusion, leading to unauthorized database access or potential privilege e
escalation.
Remediation: Implement proper name collision detection for roles and us
user accounts in the authorization system; ensure unique identifiers are us
used to distinguish between different principals when caching lookups; vali
validate that cache keys include all necessary context (connection type, ho
host, role vs user flags) before storing results.