What’s Vulnerable › Vulnerabilities

CVE-2021-47538: rxrpc: Fix rxrpc_local leak in rxrpc_lookup_peer()

• Severity: medium (CVSS 5.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2024-05-24 · updated 2026-06-17
• Weakness: CWE-401

Description

In the Linux kernel, the following vulnerability has been resolved: rxrpc: Fix rxrpc_local leak in rxrpc_lookup_peer() Need to call rxrpc_put_local() for peer candidate before kfree() as it holds a ref to rxrpc_local. [DH: v2: Changed to abstract the peer freeing code out into a function]

Affected products

• Linux kernel: from 4.19.82 before 4.19.220; from 5.3.9 before 5.4; from 5.4.1 before 5.4.164; from 5.5 before 5.10.84; from 5.11 before 5.15.7; 5.4, 5.4-rc4, 5.4-rc5, 5.4-rc6, 5.4-rc7, 5.4-rc8 (+3) — fixed in 4.19.220, 5.10.84, 5.15.7, 5.4, 5.4.164

How to fix

Upgrade to a fixed version: Linux kernel 4.19.220, 5.10.84, 5.15.7, 5.4. Check the vendor advisory for mitigations.

References

• https://git.kernel.org/stable/c/3e70e3a72d80b16094faccbe438cd53761c3503a
• https://git.kernel.org/stable/c/60f0b9c42cb80833a03ca57c1c8b078d716e71d1
• https://git.kernel.org/stable/c/913c24af2d13a3fd304462916ee98e298d56bdce
• https://git.kernel.org/stable/c/9469273e616ca8f1b6e3773c5019f21b4c8d828c
• https://git.kernel.org/stable/c/beacff50edbd6c9659a6f15fc7f6126909fade29
• https://git.kernel.org/stable/c/3e70e3a72d80b16094faccbe438cd53761c3503a
• https://git.kernel.org/stable/c/60f0b9c42cb80833a03ca57c1c8b078d716e71d1
• https://git.kernel.org/stable/c/913c24af2d13a3fd304462916ee98e298d56bdce
• https://git.kernel.org/stable/c/9469273e616ca8f1b6e3773c5019f21b4c8d828c
• https://git.kernel.org/stable/c/beacff50edbd6c9659a6f15fc7f6126909fade29

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