CVE-2023-39326
Denial of service via chunk extensions in net/http
Description
A malicious HTTP sender can use chunk extensions to cause a receiver reading from a request or response body to read many more bytes from the network than are in the body. A malicious HTTP client can further exploit this to cause a server to automatically read a large amount of data (up to about 1GiB) when a handler fails to read the entire body of a request. Chunk extensions are a little-used HTTP feature which permit including additional metadata in a request or response body sent using the chunked encoding. The net/http chunked encoding reader discards this metadata. A sender can exploit this by inserting a large metadata segment with each byte transferred. The chunk reader now produces an error if the ratio of real body to encoded bytes grows too small.
How to fix CVE-2023-39326
To remediate CVE-2023-39326, upgrade the affected package to a fixed version below.
- —upgrade to 1.20.12 or later
- —no fix listed
- —no fix listed
- —upgrade to 1.20.12 or later
Is CVE-2023-39326 being exploited?
Low — EPSS is 0.1%, meaning exploitation activity has not been observed at scale.
Affected packages (4)
- from 0, < 1.20.12, >= 1.21.0-0, < 1.21.5
- from 0
- from 0
- from 0, < 1.20.12, >= 1.21.0-0, < 1.21.5
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | MEDIUM5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N |