CVE-2026-4271: Use After Free in Red Hat Red Hat Enterprise Linux 10
CVE-2026-4271 is a Use-After-Free vulnerability in the libsoup HTTP library's HTTP/2 server implementation on Red Hat Enterprise Linux 10. A remote attacker can send specially crafted HTTP/2 requests that cause authentication failures, leading to the application accessing freed memory. This can cause application instability or crashes, resulting in a Denial of Service (DoS). The vulnerability has a CVSS score of 5.3 (medium severity). Red Hat has released security updates for libsoup3 to address this issue across multiple architectures and product variants of Red Hat Enterprise Linux 10.
AI Analysis
Technical Summary
The vulnerability CVE-2026-4271 affects libsoup, a C-based HTTP library used in Red Hat Enterprise Linux 10. It is a Use-After-Free flaw in the HTTP/2 server code path, triggered by specially crafted HTTP/2 requests that cause authentication failures. Exploitation can lead to the application attempting to access memory that has already been freed, potentially causing crashes or instability (Denial of Service). Red Hat has issued official security advisories (RHSA-2026:15968 and RHSA-2026:17482) providing updated libsoup3 packages that fix this vulnerability. The updates cover multiple architectures including x86_64, s390x, ppc64le, and aarch64, and are available for standard and extended update support versions of Red Hat Enterprise Linux 10.
Potential Impact
The vulnerability allows remote attackers to cause a Denial of Service by crashing or destabilizing applications using the vulnerable libsoup HTTP/2 server implementation. There is no impact on confidentiality or integrity according to the CVSS vector. No known exploits in the wild have been reported at this time. The impact is limited to availability disruption of affected services.
Mitigation Recommendations
Red Hat has released official security updates for libsoup3 that address CVE-2026-4271. Users of Red Hat Enterprise Linux 10 should apply the updated packages as per the advisories RHSA-2026:15968 and RHSA-2026:17482. Detailed update instructions are available at https://access.redhat.com/articles/11258. Applying these updates mitigates the vulnerability. No additional action is required beyond installing the vendor-provided patches.
CVE-2026-4271: Use After Free in Red Hat Red Hat Enterprise Linux 10
Description
CVE-2026-4271 is a Use-After-Free vulnerability in the libsoup HTTP library's HTTP/2 server implementation on Red Hat Enterprise Linux 10. A remote attacker can send specially crafted HTTP/2 requests that cause authentication failures, leading to the application accessing freed memory. This can cause application instability or crashes, resulting in a Denial of Service (DoS). The vulnerability has a CVSS score of 5.3 (medium severity). Red Hat has released security updates for libsoup3 to address this issue across multiple architectures and product variants of Red Hat Enterprise Linux 10.
CVSS v3.1
Score 5.3medium
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability CVE-2026-4271 affects libsoup, a C-based HTTP library used in Red Hat Enterprise Linux 10. It is a Use-After-Free flaw in the HTTP/2 server code path, triggered by specially crafted HTTP/2 requests that cause authentication failures. Exploitation can lead to the application attempting to access memory that has already been freed, potentially causing crashes or instability (Denial of Service). Red Hat has issued official security advisories (RHSA-2026:15968 and RHSA-2026:17482) providing updated libsoup3 packages that fix this vulnerability. The updates cover multiple architectures including x86_64, s390x, ppc64le, and aarch64, and are available for standard and extended update support versions of Red Hat Enterprise Linux 10.
Potential Impact
The vulnerability allows remote attackers to cause a Denial of Service by crashing or destabilizing applications using the vulnerable libsoup HTTP/2 server implementation. There is no impact on confidentiality or integrity according to the CVSS vector. No known exploits in the wild have been reported at this time. The impact is limited to availability disruption of affected services.
Mitigation Recommendations
Red Hat has released official security updates for libsoup3 that address CVE-2026-4271. Users of Red Hat Enterprise Linux 10 should apply the updated packages as per the advisories RHSA-2026:15968 and RHSA-2026:17482. Detailed update instructions are available at https://access.redhat.com/articles/11258. Applying these updates mitigates the vulnerability. No additional action is required beyond installing the vendor-provided patches.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- redhat
- Date Reserved
- 2026-03-16T14:43:58.712Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Vendor Advisory Urls
- [{"url":"https://access.redhat.com/security/cve/CVE-2026-4271","vendor":"Red Hat"}]
Threat ID: 69b93ad5771bdb1749a35140
Added to database: 3/17/2026, 11:28:21 AM
Last enriched: 5/26/2026, 8:47:16 PM
Last updated: 6/15/2026, 5:23:54 PM
Views: 214
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