MSRC_CVE-2021-26930

Vulnerability from csaf_microsoft - Published: 2021-02-02 00:00 - Updated: 2021-02-25 00:00
Summary
An issue was discovered in the Linux kernel 3.11 through 5.10.16 as used by Xen. To service requests to the PV backend the driver maps grant references provided by the frontend. In this process errors may be encountered. In one case an error encountered earlier might be discarded by later processing resulting in the caller assuming successful mapping and hence subsequent operations trying to access space that wasn't mapped. In another case internal state would be insufficiently updated preventing safe recovery from the error. This affects drivers/block/xen-blkback/blkback.c.

Notes

Additional Resources
To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle
Disclaimer
The information provided in the Microsoft Knowledge Base is provided \"as is\" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.
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            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "environmentalsScore": 0.0,
            "integrityImpact": "HIGH",
            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "temporalScore": 7.8,
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
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      "title": "An issue was discovered in the Linux kernel 3.11 through 5.10.16 as used by Xen. To service requests to the PV backend the driver maps grant references provided by the frontend. In this process errors may be encountered. In one case an error encountered earlier might be discarded by later processing resulting in the caller assuming successful mapping and hence subsequent operations trying to access space that wasn\u0027t mapped. In another case internal state would be insufficiently updated preventing safe recovery from the error. This affects drivers/block/xen-blkback/blkback.c."
    }
  ]
}


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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Detection rules are retrieved from Rulezet.