Advisory details:
github_osv / GHSA-6mjq-h674-j845
| Advisory ID | github_osv/GHSA-6mjq-h674-j845 |
| Aliases |
CVE-2023-34462
|
| Summary | netty-handler SniHandler 16MB allocation ### Summary The `SniHandler` can allocate up to 16MB of heap for each channel during the TLS handshake. When the handler or the channel does not have an idle timeout, it can be used to make a TCP server using the `SniHandler` to allocate 16MB of heap. ### Details The `SniHandler` class is a handler that waits for the TLS handshake to configure a `SslHandler` according to the indicated server name by the `ClientHello` record. For this matter it allocates a `ByteBuf` using the value defined in the `ClientHello` record. Normally the value of the packet should be smaller than the handshake packet but there are not checks done here and the way the code is written, it is possible to craft a packet that makes the `SslClientHelloHandler` 1/ allocate a 16MB `ByteBuf` 2/ not fail `decode` method `in` buffer 3/ get out of the loop without an exception The combination of this without the use of a timeout makes easy to connect to a TCP server and allocate 16MB of heap memory per connection. ### Impact If the user has no idle timeout handler configured it might be possible for a remote peer to send a client hello packet which lead the server to buffer up to 16MB of data per connection. This could lead to a OutOfMemoryError and so result in a DDOS. |
| Status | Published |
| Exploitability | 0.5 |
| Weighted Severity | 5.9 |
| Risk | 3.0 |
| Affected and Fixed Packages | Package Details |
| Introduced and Fixed Package Commit Patches | Package Commit Patches Details |
| System | Score | Found at |
|---|---|---|
| cvssv3.1 | 6.5 | https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2023/06/GHSA-6mjq-h674-j845/GHSA-6mjq-h674-j845.json |
| generic_textual | MODERATE |
No EPSS data available for this advisory.
| Patch URL | |
|---|---|
| There are no known patches. | |
| Attack Vector (AV) | Attack Complexity (AC) | Privileges Required (PR) | User Interaction (UI) | Scope (S) | Confidentiality Impact (C) | Integrity Impact (I) | Availability Impact (A) |
|---|---|---|---|---|---|---|---|
network adjacent_network local physical |
low high |
none low high |
none required |
unchanged changed |
high low none |
high low none |
high low none |
Vector: SSVCv2/E:N/A:N/T:P/P:M/B:A/M:M/D:T/2024-07-16T18:36:13Z/
Decision: Track
Source URL: https://github.com/cisagov/vulnrichment/blob/develop/2023/34xxx/CVE-2023-34462.json
Source Advisory: vulnrichment/CVE-2023-34462
[{'Exploitation': 'none'},
{'Automatable': 'no'},
{'Technical Impact': 'partial'},
{'Mission Prevalence': 'minimal'},
{'Public Well-being Impact': 'material'},
{'Mission & Well-being': 'medium'}]