CVE-2021-47132

mptcp: fix sk_forward_memory corruption on retransmission

Description

In the Linux kernel, the following vulnerability has been resolved: mptcp: fix sk_forward_memory corruption on retransmission MPTCP sk_forward_memory handling is a bit special, as such field is protected by the msk socket spin_lock, instead of the plain socket lock. Currently we have a code path updating such field without handling the relevant lock: __mptcp_retrans() -> __mptcp_clean_una_wakeup() Several helpers in __mptcp_clean_una_wakeup() will update sk_forward_alloc, possibly causing such field corruption, as reported by Matthieu. Address the issue providing and using a new variant of blamed function which explicitly acquires the msk spin lock.

Category

7.1
CVSS
Severity: High
CVSS 3.1 •
EPSS 0.02%
Affected: Linux Linux
Affected: Linux Linux
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2021-47132?
CVE-2021-47132 has been scored as a high severity vulnerability.
How to fix CVE-2021-47132?
To fix CVE-2021-47132, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-47132 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-47132 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-47132?
CVE-2021-47132 affects Linux Linux, Linux Linux.
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