CVE-2026-4271 (GCVE-0-2026-4271)
Vulnerability from cvelistv5 – Published: 2026-03-17 11:14 – Updated: 2026-11-05 20:46
VLAI
EPSS
VEX
Title
Libsoup: libsoup: denial of service via use-after-free in http/2 server
Summary
A flaw was found in libsoup, a library for handling HTTP requests. This vulnerability, known as a Use-After-Free, occurs in the HTTP/2 server implementation. A remote attacker can exploit this by sending specially crafted HTTP/2 requests that cause authentication failures. This can lead to the application attempting to access memory that has already been freed, potentially causing application instability or crashes, resulting in a Denial of Service (DoS).
Severity
5.3 (Medium)
SSVC
Exploitation: poc
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-17 13:04 UTC
CWE
- CWE-416 - Use After Free
Assigner
redhat
CNA
References
6 references
| URL | Tags |
|---|---|
| https://access.redhat.com/errata/RHSA-2026:15968 | vendor-advisoryx_refsource_REDHAT |
| https://access.redhat.com/errata/RHSA-2026:17482 | vendor-advisoryx_refsource_REDHAT |
| https://access.redhat.com/errata/RHSA-2026:19143 | vendor-advisoryx_refsource_REDHAT |
| https://access.redhat.com/security/cve/CVE-2026-4271 | vdb-entryx_refsource_REDHAT |
| https://bugzilla.redhat.com/show_bug.cgi?id=2448044 | issue-trackingx_refsource_REDHAT |
| https://gitlab.gnome.org/GNOME/libsoup/-/issues/496 |
Impacted products
7 products
| Vendor | Product | Version | |
|---|---|---|---|
| Red Hat | Red Hat Enterprise Linux 10 |
Unaffected:
0:3.6.5-3.el10_1.11 , < *
(rpm)
cpe:/o:redhat:enterprise_linux:10.1 |
|
| Red Hat | Red Hat Enterprise Linux 10 |
Unaffected:
0:3.6.5-3.el10_2.11 , < *
(rpm)
cpe:/o:redhat:enterprise_linux:10.2 |
|
| Red Hat | Red Hat Enterprise Linux 10.0 Extended Update Support |
Unaffected:
0:3.6.5-3.el10_0.15 , < *
(rpm)
cpe:/o:redhat:enterprise_linux_eus:10.0 |
|
| Red Hat | Red Hat Enterprise Linux 6 |
cpe:/o:redhat:rhel_els:6
|
|
| Red Hat | Red Hat Enterprise Linux 7 |
cpe:/o:redhat:rhel_els:7
|
|
| Red Hat | Red Hat Enterprise Linux 8 |
cpe:/a:redhat:enterprise_linux:8
|
|
| Red Hat | Red Hat Enterprise Linux 9 |
cpe:/a:redhat:enterprise_linux:9
|
Date Public
2026-03-16 00:00
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