CVE-2026-1801
published 2026-02-03CVE-2026-1801: A flaw was found in libsoup, an HTTP client/server library. This HTTP Request Smuggling vulnerability arises from non-RFC-compliant parsing in the…
PriorityP338medium6.5CVSS 3.1
AVNACLPRNUINSUCLILAN
EPSS
0.38%
29.9th percentile
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.
Affected
7 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | libsoup2.4 | < libsoup3 3.6.5-8 (forky) | libsoup3 3.6.5-8 (forky) |
| debian | libsoup3 | < libsoup3 3.6.5-8 (forky) | libsoup3 3.6.5-8 (forky) |
| redhat | enterprise_linux | — | — |
| redhat | enterprise_linux | — | — |
| redhat | enterprise_linux | — | — |
| redhat | enterprise_linux | — | — |
| redhat | enterprise_linux | — | — |
CVSS provenance
nvdv3.16.5MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
osv6.5MEDIUM
vendor_debian5.3MEDIUM
vendor_redhat5.3MEDIUM
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Red Hat
libsoup: libsoup: HTTP Request Smuggling via malformed chunk headers
vendor_redhat·2026-02-03·CVSS 5.3
CVE-2026-1801 [MEDIUM] CWE-444 libsoup: libsoup: HTTP Request Smuggling via malformed chunk headers
libsoup: libsoup: HTTP Request Smuggling via malformed chunk headers
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.
A flaw was found in libsoup, an HTTP client/server library. This HTTP Request Smuggling vulnerability arises from non-RFC-c
Debian
CVE-2026-1801: libsoup2.4 - A flaw was found in libsoup, an HTTP client/server library. This HTTP Request Sm...
vendor_debian·2026·CVSS 5.3
CVE-2026-1801 [MEDIUM] CVE-2026-1801: libsoup2.4 - A flaw was found in libsoup, an HTTP client/server library. This HTTP Request Sm...
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.
Scope: local
bookworm: open
bullseye: open
trixie: open
GHSA
GHSA-xv49-34rf-rqv4: A flaw was found in libsoup, an HTTP client/server library
ghsa_unreviewed·2026-02-03
CVE-2026-1801 [MEDIUM] CWE-444 GHSA-xv49-34rf-rqv4: A flaw was found in libsoup, an HTTP client/server library
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.
OSV
CVE-2026-1801: A flaw was found in libsoup, an HTTP client/server library
osv·2026-02-03·CVSS 6.5
CVE-2026-1801 [MEDIUM] CVE-2026-1801: A flaw was found in libsoup, an HTTP client/server library
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.
No detection rules found.
No public exploits indexed.
Wiz
CVE-2026-1801 Impact, Exploitability, and Mitigation Steps | Wiz
blogs_wiz·CVSS 5.3
CVE-2026-1801 [MEDIUM] CVE-2026-1801 Impact, Exploitability, and Mitigation Steps | Wiz
## CVE-2026-1801 :
CBL Mariner vulnerability analysis and mitigation
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.
Source : NVD
## 6.5
Score
Published February 3, 2026
Severity MEDIUM
CNA Score 5.3
Affected Technologies
CBL Mari
Bugzilla
CVE-2026-1801 libsoup: libsoup: HTTP Request Smuggling via malformed chunk headers
bugzilla·2026-02-03·CVSS 6.5
CVE-2026-1801 [MEDIUM] CVE-2026-1801 libsoup: libsoup: HTTP Request Smuggling via malformed chunk headers
CVE-2026-1801 libsoup: libsoup: HTTP Request Smuggling via malformed chunk headers
HTTP Request Smuggling vulnerability in the chunked transfer encoding parser of the libsoup HTTP library. The flaw is caused by non-RFC-compliant parsing in the soup_filter_input_stream_read_line() logic, where libsoup accepts lone LF (\n) characters and other malformed chunk headers instead of enforcing CRLF (\r\n) as required by RFC 9112. When a malicious HTTP client sends specially crafted chunked requests, libsoup may parse and process multiple HTTP requests from a single network message. Although exploitation is possible remotely without authentication or user interaction, the impact is limited because SoupServer is not commonly used in internet-facing infrastructure.
2026-02-03
Published