CVE Catalog

CVE-2021-47132

HighCVSS 7.5
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.48%

39th percentile - higher than 39% of all known CVEs

Summary

In the Linux kernel, the MPTCP protocol has a corruption of the sk_forward_memory field during retransmission. This field is protected by the msk socket spin_lock, but a code path updates it without that lock, potentially leading to data corruption.

Risk Assessment

This could cause unpredictable behavior of MPTCP connections, including data loss or system crash.

Recommendation

Install the Linux kernel patch that adds proper spin_lock protection in __mptcp_clean_una_wakeup().

Other vulnerabilities in Linux kernel

See all
Original NVD description (English source)

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.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS