FlawAtlas
Search the atlas
CVE-2021-37137 High

SnappyFrameDecoder doesn't restrict chunk length any may buffer skippable chunks in an unnecessary way

### Impact The Snappy frame decoder function doesn't restrict the chunk length which may lead to excessive memory usage. Beside this it also may buffer reserved skippable chunks until the whole chunk was received which may lead to excessive memory usage as well. This vulnerability can be triggered by supplying malicious input that decompresses to a very big size (via a network stream or a file) or by sending a huge skippable chunk. ### Impact All users of SnappyFrameDecoder are affected and so the application may be in risk for a DoS attach due excessive memory usage. ### References https://github.com/netty/netty/blob/netty-4.1.67.Final/codec/src/main/java/io/netty/handler/codec/compression/SnappyFrameDecoder.java#L79 https://github.com/netty/netty/blob/netty-4.1.67.Final/codec/src/main/java/io/netty/handler/codec/compression/SnappyFrameDecoder.java#L171 https://github.com/netty/netty/blob/netty-4.1.67.Final/codec/src/main/java/io/netty/handler/codec/compression/SnappyFrameDecoder.java#L185

Exploit probability 6.3%
Published September 9, 2021
Required by Not available
Last source change July 8, 2026

02 / AFFECTED SOFTWARE

Affected packages

Maven io.netty:netty

71 explicit affected versions

Maven io.netty:netty-codec

141 explicit affected versions

Maven org.jboss.netty:netty

39 explicit affected versions

Unknown Unknown

118 explicit affected versions

03 / CONNECTIONS

Connected vulnerabilities

04 / EVIDENCE

Source records

Open Source Vulnerabilities GHSA-9vjp-v76f-g363

### Impact The Snappy frame decoder function doesn't restrict the chunk length which may lead to excessive memory usage. Beside this it also may buffer reserved skippable chunks until the whole chunk was received which may lead to excessive memory usage as well. This vulnerability can be triggered by supplying malicious input that decompresses to a very big size (via a network stream or a file) or by sending a huge skippable chunk. ### Impact All users of SnappyFrameDecoder are affected and so the application may be in risk for a DoS attach due excessive memory usage. ### References https://github.com/netty/netty/blob/netty-4.1.67.Final/codec/src/main/java/io/netty/handler/codec/compression/SnappyFrameDecoder.java#L79 https://github.com/netty/netty/blob/netty-4.1.67.Final/codec/src/main/java/io/netty/handler/codec/compression/SnappyFrameDecoder.java#L171 https://github.com/netty/netty/blob/netty-4.1.67.Final/codec/src/main/java/io/netty/handler/codec/compression/SnappyFrameDecoder.java#L185

View original source
Open Source Vulnerabilities CVE-2021-37137

The Snappy frame decoder function doesn't restrict the chunk length which may lead to excessive memory usage. Beside this it also may buffer reserved skippable chunks until the whole chunk was received which may lead to excessive memory usage as well. This vulnerability can be triggered by supplying malicious input that decompresses to a very big size (via a network stream or a file) or by sending a huge skippable chunk.

View original source

05 / REFERENCES

Further evidence