CVE-2021-47152

CVE-2021-47152 is a medium-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-787.

Key facts

Description

In the Linux kernel, the following vulnerability has been resolved: mptcp: fix data stream corruption Maxim reported several issues when forcing a TCP transparent proxy to use the MPTCP protocol for the inbound connections. He also provided a clean reproducer. The problem boils down to 'mptcp_frag_can_collapse_to()' assuming that only MPTCP will use the given page_frag. If others - e.g. the plain TCP protocol - allocate page fragments, we can end-up re-using already allocated memory for mptcp_data_frag. Fix the issue ensuring that the to-be-expanded data fragment is located at the current page frag end. v1 -> v2: - added missing fixes tag (Mat)

Frequently asked questions

What is CVE-2021-47152?
In the Linux kernel, the following vulnerability has been resolved: mptcp: fix data stream corruption Maxim reported several issues when forcing a TCP transparent proxy to use the MPTCP protocol for the inbound connections. He also provided a clean reproducer. The problem boils down to 'mptcp_frag_can_collapse_to()' assuming that only MPTCP will use the given page_frag. If others - e.g. the plain TCP protocol - allocate page fragments, we can end-up re-using already allocated memory for mptcp_data_frag. Fix the issue ensuring that the to-be-expanded data fragment is located at the current page frag end. v1 -> v2: - added missing fixes tag (Mat)
How severe is CVE-2021-47152?
CVE-2021-47152 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-47152 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (14th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-47152?
CVE-2021-47152 primarily affects Linux Linux Kernel. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-47152?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2021-47152 have an EU (EUVD) identifier?
Yes. CVE-2021-47152 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-33800.
When was CVE-2021-47152 published?
CVE-2021-47152 was published on 2024-03-25 and last updated on 2026-06-17.

References

Affected products (4)

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