Netty: Denial of Service in XmlFrameDecoder via CPU Exhaustion
An attacker can cause Denial of Service by sending a specially crafted malicious XML payload (e.g., repeated </ characters) to a Netty server utilizing XmlFrameDecoder, causing the server's EventLoop thread to exhaust CPU resources and become unresponsive.
io.netty.handler.codec.xml.XmlFrameDecoder suffers from a vulnerability resulting in CPU exhaustion. When < followed by / is encountered, the decoder scans the remaining buffer for a closing >.
Because the parser state is not saved between decode() invocations, an attacker can trickle-feed a payload of </ characters. This forces the decoder to repeatedly rescan the entire accumulated buffer. A 1MB maxFrameLength is enough to completely hang a server's thread while it loops endlessly.
Denial of Service via CPU Exhaustion. Any application utilizing Netty's XmlFrameDecoder is impacted. An unauthenticated remote attacker can exploit this flaw by sending a modest amount of malformed XML data to an exposed port.
왜 이 VPI인가 (설명가능 · 실험적)
VPI 산정 기준
| 영향도 | 75.00 |
| 악용 신호(추가 악용신호 없음) | ×1.00 |
| VPI | 75.00 |
VPI 공식 vpi-v1 기준