CVE-2026-1801 (GCVE-0-2026-1801)

Vulnerability from cvelistv5 – Published: 2026-02-03 20:12 – Updated: 2026-03-26 18:58
VLAI
Title
Libsoup: libsoup: http request smuggling via malformed chunk headers
Summary
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.
Severity
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-444 - Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')
Assigner
References
Impacted products
Date Public
2026-02-03 00:00
Credits
Red Hat would like to thank Ahmed Lekssays for reporting this issue.
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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