Skip to main content

Libsoup CVE-2026-1801

MEDIUM
HTTP Request/Response Smuggling (CWE-444)
2026-02-03 secalert@redhat.com
Information Disclosure Red Hat Request Smuggling Enterprise Linux Suse Libsoup Gnome
5.3
CVSS 3.1 · NVD
View

Vulnerability Assessment

Weakness
CWE
CWE-444
OWASP Top 10:2025
A06:2025 - Insecure Design
ASVS 5.0
V4 - API and Web Service HTTP request consistency
Impact

CVSS 5.3 (MEDIUM). Attack vector: Network. Complexity: Low. Privileges required: None. User interaction: None. Exploitation no authentication required. Exploitable via remote/network.
Exploit ScenarioDerived

A remote attacker without authentication could exploit this flaw, information disclosure.
This Month Plan within 30 days. Why: MEDIUM severity (CVSS 4.0-6.9).
Patch available 0.0% exploitation probability (EPSS)

Get an e-mail when this CVE is exploited, patched or re-scored. Free account.

Alert me

AnalysisAIv1 – Mar 12, 2026

HTTP request smuggling in libsoup allows remote attackers to exploit non-compliant chunk header parsing by injecting malformed requests with LF-only line endings instead of proper CRLF formatting. Without requiring authentication, an attacker can cause libsoup to interpret multiple HTTP requests from a single network message, potentially leading to information disclosure. No patch is currently available for this vulnerability.

Earlier versions of this analysis (1)
v1 Mar 12, 2026 - 21:54 CVSS 5.3

A flaw was found in libsoup, an HTTP client/server library. [CVSS 5.3 MEDIUM]

RemediationAI

Monitor vendor advisories for a patch. Restrict network access to the affected service where possible.

Affects your stack

Find out whether the stacks and servers you run are on an affected version.

Checking this CVE against your own stacks and servers is part of the Basic plan and up.

Sign in to check
Technical ContextAI · show details

Classified as CWE-444 (HTTP Request/Response Smuggling). 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 pro

Know when Libsoup gets its next vulnerability

  • Watch products and get an email when something new is published
  • Check this CVE against your own stack and servers
  • Exploit and PoC references, threat intelligence from 22 sources
Continue with Google Continue with GitHub

No credit card · 7-day full trial

Severity by source

NVD PRIMARY 5.3 MEDIUM
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
SUSE MEDIUM
Red Hat 5.3 LOW

Primary rating from NVD.

CVSS VectorNVD

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
Low
Availability
None

Lifecycle Timeline

2
Patch released
Apr 09, 2026 - 14:30 nvd
Patch available
CVE Published
Feb 03, 2026 - 21:16 nvd
MEDIUM 5.3

DescriptionCVE.org

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.

Executive ViewAI

Why It Matters

Organizations using A flaw should be aware of moderate risk from CVE-2026-1801 rated CVSS 5.3. Exploitation could compromise the security of affected deployments. Organizations should apply vendor updates when available and monitor for exploitation.

Business Impact: Low
Compensating Controls

Apply vendor patch. If patching is delayed: restrict network access and enable monitoring.

Threat Intelligence Overview

EPSS Score
0.0%
Top 89% exploitable
Data Quality
3 sources
Confidence: Low
NVD CVE.org EPSS Vendor VulDB

How this decision was reached

The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.

SignalValue
Severity MEDIUM
CISA KEV No
Public POC No
EPSS 0.0%
Patch available Yes
Active threat No
Deciding rule
MEDIUM severity (CVSS 4.0-6.9)
What every action level means
Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.
Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.
This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.
This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.
Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.

SSVC AssessmentENISA

SSVC Decision· derived
Scheduled
Exploitation· derived
None
System Exposure· derived
Open
Automatable· derived
Yes
Human Impact
Low

Priority Score

26
Low Medium High Critical
KEV: 0
EPSS: 0
CVSS: +26
PoC: 0
Weaponized: 0
Threat intel: 0
Gov advisory: 0

Attack Technique

HTTP Request Smuggling HIGH

HTTP request smuggling exploits inconsistencies in how front-end and back-end servers parse HTTP message boundaries.

Information Disclosure MEDIUM

Information disclosure occurs when an application unintentionally exposes sensitive data that aids attackers in reconnaissance or directly compromises security.

Affected Products (CPE)CVE.org

cpe:2.3:a:gnome:libsoup:-:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:6.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:10.0:*:*:*:*:*:*:*

More in Libsoup

View all
CVE-2019-17266 CRITICAL POC
9.8 Oct 06

libsoup from versions 2.65.1 until 2.68.1 have a heap-based buffer over-read because soup_ntlm_parse_challenge() in soup
CVE-2024-52530 HIGH POC
7.5 Nov 11

GNOME libsoup before 3.6.0 allows HTTP request smuggling in some configurations because '\0' characters at the end of he
CVE-2025-2784 MEDIUM POC
6.5 Apr 03

A flaw was found in libsoup. Rated high severity (CVSS 7.0), this vulnerability is remotely exploitable, no authenticati
CVE-2024-52531 MEDIUM POC
6.5 Nov 11

GNOME libsoup before 3.6.1 allows a buffer overflow in applications that perform conversion to UTF-8 in soup_header_pars
CVE-2026-102560 CRITICAL
9.8 Sep 29

A heap buffer overflow exists in libsoup's WebSocket permessage-deflate compression path: when a very large outbound mes
CVE-2026-1536 MEDIUM POC
5.8 Jan 28

HTTP header injection in libsoup through CRLF sequences in the Content-Disposition header allows unauthenticated remote

CVE-2026-1467 MEDIUM POC
5.8 Jan 27

libsoup's improper handling of URL-decoded input in HTTP proxy configurations allows remote attackers to inject CRLF seq
CVE-2018-12910 CRITICAL
9.8 Jul 05

The get_cookies function in soup-cookie-jar.c in libsoup 2.63.2 allows attackers to have unspecified impact via an empty
CVE-2026-102559 HIGH
8.6 Sep 29

Heap memory corruption in libsoup can be triggered when a WebSocket client using libsoup constructs a masked outgoing fr
CVE-2026-102558 HIGH
8.6 Sep 29

Heap out-of-bounds read in libsoup's WebSocket implementation allows a remote, unauthenticated peer to trigger a heap bu
CVE-2026-102557 HIGH
8.6 Sep 29

Heap corruption and denial of service in libsoup stem from unbounded WebSocket message reassembly: the code accumulates

CVE-2026-102556 HIGH
8.6 Sep 29

A type-confusion memory-safety flaw in libsoup's WebSocket handling can crash or corrupt the heap of applications that p

Same weakness CWE-444 – HTTP Request/Response Smuggling

View all
CVE-2023-41265 CRITICAL POC
9.9
CVE-2026-88773 CRITICAL POC
9.3
CVE-2026-48710 MEDIUM POC
6.5
CVE-2021-33037 MEDIUM
5.3
CVE-2021-23336 MEDIUM POC
5.9
CVE-2025-55315 CRITICAL POC
9.9
CVE-2018-3907 CRITICAL POC
10.0
CVE-2024-10264 CRITICAL POC
9.8

Same technique Information Disclosure

View all
CVE-2019-2725 CRITICAL POC
9.8
CVE-2021-34523 CRITICAL POC
9.0
CVE-2013-2251 CRITICAL POC
9.8
CVE-2017-5638 CRITICAL POC
9.8
CVE-2025-24813 CRITICAL POC
9.8
CVE-2025-68613 HIGH POC
8.8
CVE-2015-1701 HIGH POC
7.8
CVE-2017-0147 HIGH POC
7.5

Vendor StatusVendor

SUSE

Severity: Medium
Product Status
SUSE Linux Enterprise Desktop 15 SP7 Fixed
SUSE Linux Enterprise Desktop 15 SP7 Fixed
SUSE Linux Enterprise High Performance Computing 15 SP7 Fixed
SUSE Linux Enterprise High Performance Computing 15 SP7 Fixed
SUSE Linux Enterprise Micro 5.2 Fixed

References

Advisories & patches
ADVISORY https://ubuntu.com/security/notices/USN-8780-1 ADVISORY https://vuldb.com/?id.344157 REF https://access.redhat.com/security/cve/CVE-2026-1801 REF https://bugzilla.redhat.com/show_bug.cgi?id=2436315 REF https://gitlab.gnome.org/GNOME/libsoup/-/issues/481

Search Externally

GitHub PoC Exploit-DB PacketStorm Snyk Rapid7 Nuclei Templates Trickest PoC
Back

This site uses cookies essential for authentication and security. No tracking or analytics cookies are used. Privacy Policy