CVE-2025-14523 Libsoup: libsoup: duplicate host header handling causes host-parsing discrepancy (first- vs last-value wins)
Attackers can exploit Host header discrepancies in libsoup to bypass access controls or poison caches via request smuggling.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-14523?
CVE-2025-14523 is a high-severity vulnerability in Red Hat Enterprise Linux 10, published on 11 Dec 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
A flaw in libsoup’s HTTP header handling allows multiple Host: headers in a request and returns the last occurrence for server-side processing. Common front proxies often honor the first Host: header, so this mismatch can cause vhost confusion where a proxy routes a request to one backend but the backend interprets it as destined for another host. This discrepancy enables request-smuggling style attacks, cache poisoning, or bypassing host-based access controls when an attacker supplies duplicate Host headers.
Weakness: CWE-444
Which versions are affected by CVE-2025-14523?
Linux distribution packages (40)
libsoup3-doc AlmaLinux:10 | All versions | 3.6.5-3.el10_1.8 |
libsoup AlmaLinux:8 | All versions | 2.62.3-11.el8_10 |
libsoup-devel AlmaLinux:8 | All versions | 2.62.3-11.el8_10 |
libsoup AlmaLinux:9 | All versions | 2.72.0-12.el9_7.3 |
libsoup-devel AlmaLinux:9 | All versions | 2.72.0-12.el9_7.3 |
libsoup3 Red Hat:enterprise_linux:10.1 | All versions | 0:3.6.5-3.el10_1.8 |
libsoup3-debuginfo Red Hat:enterprise_linux:10.1 | All versions | 0:3.6.5-3.el10_1.8 |
libsoup3-debugsource Red Hat:enterprise_linux:10.1 | All versions | 0:3.6.5-3.el10_1.8 |
libsoup3-devel Red Hat:enterprise_linux:10.1 | All versions | 0:3.6.5-3.el10_1.8 |
libsoup3-doc Red Hat:enterprise_linux:10.1 | All versions | 0:3.6.5-3.el10_1.8 |
libsoup-debuginfo Red Hat:enterprise_linux:8::appstream | All versions | 0:2.62.3-11.el8_10 |
libsoup-debugsource Red Hat:enterprise_linux:8::appstream | All versions | 0:2.62.3-11.el8_10 |
libsoup-devel Red Hat:enterprise_linux:8::appstream | All versions | 0:2.62.3-11.el8_10 |
spice-client-win Red Hat:enterprise_linux:8::appstream | All versions | 0:8.10-6.el8_10.1 |
spice-client-win-x64 Red Hat:enterprise_linux:8::appstream | All versions | 0:8.10-6.el8_10.1 |
spice-client-win-x86 Red Hat:enterprise_linux:8::appstream | All versions | 0:8.10-6.el8_10.1 |
libsoup Red Hat:enterprise_linux:8::baseos | All versions | 0:2.62.3-11.el8_10 |
libsoup-debuginfo Red Hat:enterprise_linux:8::baseos | All versions | 0:2.62.3-11.el8_10 |
libsoup-debugsource Red Hat:enterprise_linux:8::baseos | All versions | 0:2.62.3-11.el8_10 |
libsoup Red Hat:enterprise_linux:9::appstream | All versions | 0:2.72.0-12.el9_7.3 |
libsoup-debuginfo Red Hat:enterprise_linux:9::appstream | All versions | 0:2.72.0-12.el9_7.3 |
libsoup-debugsource Red Hat:enterprise_linux:9::appstream | All versions | 0:2.72.0-12.el9_7.3 |
libsoup-devel Red Hat:enterprise_linux:9::appstream | All versions | 0:2.72.0-12.el9_7.3 |
libsoup3 Red Hat:enterprise_linux_eus:10.0 | All versions | 0:3.6.5-3.el10_0.11 |
libsoup3-debuginfo Red Hat:enterprise_linux_eus:10.0 | All versions | 0:3.6.5-3.el10_0.11 |
libsoup3-debugsource Red Hat:enterprise_linux_eus:10.0 | All versions | 0:3.6.5-3.el10_0.11 |
libsoup3-devel Red Hat:enterprise_linux_eus:10.0 | All versions | 0:3.6.5-3.el10_0.11 |
libsoup3-doc Red Hat:enterprise_linux_eus:10.0 | All versions | 0:3.6.5-3.el10_0.11 |
libsoup-debuginfo Red Hat:rhel_aus:8.2::appstream | All versions | 0:2.62.3-1.el8_2.7 |
libsoup-debugsource Red Hat:rhel_aus:8.2::appstream | All versions | 0:2.62.3-1.el8_2.7 |
libsoup-devel Red Hat:rhel_aus:8.2::appstream | All versions | 0:2.62.3-1.el8_2.7 |
spice-client-win Red Hat:rhel_aus:8.2::appstream | All versions | 0:8.10-6.el8_2.1 |
spice-client-win-x64 Red Hat:rhel_aus:8.2::appstream | All versions | 0:8.10-6.el8_2.1 |
spice-client-win-x86 Red Hat:rhel_aus:8.2::appstream | All versions | 0:8.10-6.el8_2.1 |
libsoup Red Hat:rhel_aus:8.2::baseos | All versions | 0:2.62.3-1.el8_2.7 |
libsoup-debuginfo Red Hat:rhel_aus:8.2::baseos | All versions | 0:2.62.3-1.el8_2.7 |
libsoup-debugsource Red Hat:rhel_aus:8.2::baseos | All versions | 0:2.62.3-1.el8_2.7 |
libsoup-debuginfo Red Hat:rhel_aus:8.4::appstream | All versions | 0:2.62.3-2.el8_4.7 |
libsoup-debugsource Red Hat:rhel_aus:8.4::appstream | All versions | 0:2.62.3-2.el8_4.7 |
libsoup-devel Red Hat:rhel_aus:8.4::appstream | All versions | 0:2.62.3-2.el8_4.7 |
How do I fix CVE-2025-14523?
Apply the vendor's patch.
Is CVE-2025-14523 being exploited?
There is no known exploitation of CVE-2025-14523 in the wild and no public exploit code.
Sources
Also known as ALSA-2026:0421, ALSA-2026:0422, ALSA-2026:0423, AZL-72292, AZL-72302, CLSA-2026-1768555539 and 36 more.