GHSA-fj7c-vg2v-ccrm CVE-2021-3690
Undertow vulnerable to memory exhaustion due to buffer leak
High
Maven
- Severity
- 7.5 / 10
- High · CVSS 3.1
- Exploit chance (EPSS)
- 1.77%
- Chance of exploitation in the next 30 days. Higher than 78.19% of scored vulnerabilities.
- Known exploited
- No
- Not in CISA's catalog
- Weakness
- CWE-400 Uncontrolled Resource Consumption
- CWE-401 Missing Release of Memory after Effective Lifetime
- Fix
2.0.40- Upgrade io.undertow:undertow-core to this version or later
Description
Buffer leak on incoming WebSocket PONG message(s) in Undertow before 2.0.40 and 2.2.10 can lead to memory exhaustion and allow a denial of service.
Affected versions
Maven
| Package | Vulnerable | Fixed in |
|---|---|---|
| io.undertow:undertow-core | < 2.0.40 |
2.0.40 |
| io.undertow:undertow-core | >= 2.2.0, < 2.2.10 |
2.2.10 |
How to fix
Move to the fixed version or later with your package manager, update the lockfile, and run your tests. If the package only arrives through another dependency, upgrade that dependency first. If none of its releases pulls a fixed version yet, force the version with your package manager's override.
io.undertow:undertow-core Maven → 2.0.40
- maven
<dependency><groupId>io.undertow</groupId><artifactId>undertow-core</artifactId><version>2.0.40</version></dependency>- gradle
implementation("io.undertow:undertow-core:2.0.40")
Severity breakdown
CVSS 3.1 7.5
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Weakness
CWE-400: Uncontrolled Resource Consumption
The product does not properly control the allocation and maintenance of a limited resource.
How to prevent it
- Architecture and Design: Design throttling mechanisms into the system architecture. The best protection is to limit the amount of resources that an unauthorized user can cause to be expended. A strong authentication and access control model will help prevent such attacks from occurring in the first place. The login application should be protected against DoS attacks as much as possible. Limiting the database access, perhaps by caching result sets, can help minimize the resources expended. To further limit the potential for a DoS attack, consider tracking the rate of requests received from users and blocking requests that exceed a defined rate threshold.
- Architecture and Design: Mitigation of resource exhaustion attacks requires that the target system either: recognizes the attack and denies that user further access for a given amount of time, or uniformly throttles all requests in order to make it more difficult to consume resources more quickly than they can again be freed. The first of these solutions is an issue in itself though, since it may allow attackers to prevent the use of the system by a particular valid user. If the attacker impersonates the valid user, they may be able to prevent the user from accessing the server in question. The second solution is simply difficult to effectively institute -- and even when properly done, it does not provide a full solution. It simply makes the attack require more resources on the part of the attacker.
- Architecture and Design: Ensure that protocols have specific limits of scale placed on them.
- Implementation: Ensure that all failures in resource allocation place the system into a safe posture.
CWE-401: Missing Release of Memory after Effective Lifetime
The product does not sufficiently track and release allocated memory after it has been used, making the memory unavailable for reallocation and reuse.
How to prevent it
- Implementation: Choose a language or tool that provides automatic memory management, or makes manual memory management less error-prone. For example, glibc in Linux provides protection against free of invalid pointers. When using Xcode to target OS X or iOS, enable automatic reference counting (ARC) [REF-391]. To help correctly and consistently manage memory when programming in C++, consider using a smart pointer class such as std::auto_ptr (defined by ISO/IEC ISO/IEC 14882:2003), std::shared_ptr and std::unique_ptr (specified by an upcoming revision of the C++ standard, informally referred to as C++ 1x), or equivalent solutions such as Boost.
- Architecture and Design: Use an abstraction library to abstract away risky APIs. Not a complete solution.
- Architecture and Design, Build and Compilation: Consider using the Boehm-Demers-Weiser garbage collector (bdwgc), which can help avoid leaks.
References
Advisories
Packages
Other links
Timeline
- Published
- Last updated by the source
- Latest EPSS score
Related advisories
| Advisory | Severity | Why it's related |
|---|---|---|
| GHSA-3x3v-w654-m28m Undertow: Denial of Service via Multipart/Form-Data Parsing on HTTP GET Requests | Medium | Also affects io.undertow:undertow-core |
| GHSA-33hj-rcmx-86mv Undertow Servlets Vulnerable to Remote DoS via OutOfMemoryError when Passed Large Parameter Names | High | Also affects io.undertow:undertow-core |
| GHSA-j382-5jj3-vw4j Undertow HTTP server core doesn't properly validate the Host header in incoming HTTP requests | Critical | Also affects io.undertow:undertow-core |
| GHSA-6h4f-pj3g-q8fq Undertow OutOfMemory when parsing form data encoding with application/x-www-form-urlencoded | High | Also affects io.undertow:undertow-core |
| GHSA-95h4-w6j8-2rp8 Undertow MadeYouReset HTTP/2 DDoS Vulnerability | High | Also affects io.undertow:undertow-core |
| GHSA-3jrv-jgp8-45v3 Undertow incorrectly parses cookies | High | Also affects io.undertow:undertow-core |
| GHSA-97cq-f4jm-mv8h Undertow Denial of Service vulnerability | High | Also affects io.undertow:undertow-core |
| GHSA-9623-mqmm-5rcf Undertow vulnerable to Race Condition | High | Also affects io.undertow:undertow-core |
MergeHarbor checks every repository's dependencies against this database, ranks what matters by exploitability and reachability, routes it to the owning team and opens the fix pull request.
Check your repos with MergeHarbor