CVE-2026-1801
Publication date 3 February 2026
Last updated 18 September 2026
Ubuntu priority
Description
A flaw was found in libsoup, an HTTP client/server library. This HTTP Request Smuggling vulnerability arises from non-RFC-compliant parsing in the soup_filter_input_stream_read_line() logic, where libsoup accepts malformed chunk headers, such as lone line feed (LF) characters instead of the required carriage return and line feed (CRLF). A remote attacker can exploit this without authentication or user interaction by sending specially crafted chunked requests. This allows libsoup to parse and process multiple HTTP requests from a single network message, potentially leading to information disclosure.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| libsoup2.4 | 26.04 LTS resolute |
Fixed 2.74.3-10.1ubuntu5+esm2
|
| 24.04 LTS noble |
Fixed 2.74.3-6ubuntu1.8
|
|
| 22.04 LTS jammy |
Fixed 2.74.2-3ubuntu0.8
|
|
| 20.04 LTS focal |
Fixed 2.70.0-1ubuntu0.5+esm3
|
|
| 18.04 LTS bionic |
Fixed 2.62.1-1ubuntu0.4+esm8
|
|
| 16.04 LTS xenial |
Fixed 2.52.2-1ubuntu0.3+esm7
|
|
| libsoup3 | 26.04 LTS resolute |
Not affected
|
| 24.04 LTS noble |
Fixed 3.4.4-5ubuntu0.8
|
|
| 22.04 LTS jammy |
Fixed 3.0.7-0ubuntu1+esm8
|
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CVSS version: CVSS v3.0
Base score
5.3 · Medium
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
References
Related Ubuntu Security Notices (USN)
- USN-8780-1
- libsoup vulnerabilities
- 17 September 2026