Xen 4.17.x/4.18.x Flags Recovery denial of service

CVSS Meta Temp Score
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CTI Interest Score
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5.3$0-$5k0.00

Summaryinfo

A vulnerability was found in Xen 4.17.x/4.18.x and classified as critical. This affects an unknown part of the component Flags Recovery Handler. The manipulation results in denial of service. This vulnerability is cataloged as CVE-2025-27465. The attack must be initiated from a local position. There is no exploit available. A patch should be applied to remediate this issue.

Detailsinfo

A vulnerability classified as critical has been found in Xen 4.17.x/4.18.x. Affected is an unknown code of the component Flags Recovery Handler. The manipulation with an unknown input leads to a denial of service vulnerability. CWE is classifying the issue as CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. This is going to have an impact on availability. CVE summarizes:

Certain instructions need intercepting and emulating by Xen. In some cases Xen emulates the instruction by replaying it, using an executable stub. Some instructions may raise an exception, which is supposed to be handled gracefully. Certain replayed instructions have additional logic to set up and recover the changes to the arithmetic flags. For replayed instructions where the flags recovery logic is used, the metadata for exception handling was incorrect, preventing Xen from handling the the exception gracefully, treating it as fatal instead.

The advisory is available at xenbits.xen.org. This vulnerability is traded as CVE-2025-27465 since 02/26/2025. The exploitability is told to be easy. Local access is required to approach this attack. The technical details are unknown and an exploit is not available.

The vulnerability scanner Nessus provides a plugin with the ID 242155 (SUSE SLES15 Security Update : xen (SUSE-SU-2025:02319-1)), which helps to determine the existence of the flaw in a target environment.

Applying a patch is able to eliminate this problem.

The vulnerability is also documented in the databases at Tenable (242155), EUVD (EUVD-2025-21593) and CERT Bund (WID-SEC-2025-1447). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Affected

  • SUSE Linux
  • SUSE openSUSE
  • Citrix Systems XenServer
  • Open Source Xen

Productinfo

Type

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.5
VulDB Meta Temp Score: 5.3

VulDB Base Score: 5.5
VulDB Temp Score: 5.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Denial of service
CWE: CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: No

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 242155
Nessus Name: SUSE SLES15 Security Update : xen (SUSE-SU-2025:02319-1)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔒

Timelineinfo

02/26/2025 CVE reserved
07/01/2025 +124 days Advisory disclosed
07/01/2025 +0 days VulDB entry created
01/14/2026 +196 days VulDB entry last update

Sourcesinfo

Advisory: xenbits.xen.org
Status: Confirmed

CVE: CVE-2025-27465 (🔒)
GCVE (CVE): GCVE-0-2025-27465
GCVE (VulDB): GCVE-100-314514
EUVD: 🔒
CERT Bund: WID-SEC-2025-1447 - Xen: Schwachstelle ermöglicht Denial of Service

Entryinfo

Created: 07/01/2025 14:48
Updated: 01/14/2026 00:58
Changes: 07/01/2025 14:48 (52), 07/16/2025 13:16 (2), 07/16/2025 13:41 (1), 07/17/2025 00:59 (1), 07/23/2025 16:19 (7), 01/14/2026 00:58 (1)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Discussion

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