7.8

CVE-2021-47012: RDMA/siw: Fix a use after free in siw_alloc_mr

Modified
AliasesUBUNTU-CVE-2021-47012DEBIAN-CVE-2021-47012
Published 28-02-2024Last modified 05-08-2026

Vulnerability summary

CVE-2021-47012 is a high (CVSS 7.8) Use After Free vulnerability in linux. EPSS estimates a 0.27% chance of exploitation in the next 30 days, higher than 19.3% of scored vulnerabilities.

Priority
Routine

Not severe (CVSS 7.8, local access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
7.8/10
010
High · v3.1 (CVE.org)
EPSS score
0.27%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 3 · Related 3
SUSE-SU-2024:0856-1SUSE-SU-2024:0857-1SUSE-SU-2024:0926-1

Timeline

  1. 28-02-2024
    PublishedVulnerability first disclosed.
  2. 05-08-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: RDMA/siw: Fix a use after free in siw_alloc_mr Our code analyzer reported a UAF. In siw_alloc_mr(), it calls siw_mr_add_mem(mr,..). In the implementation of siw_mr_add_mem(), mem is assigned to mr->mem and then mem is freed via kfree(mem) if xa_alloc_cyclic() failed. Here, mr->mem still point to a freed object. After, the execution continue up to the err_out branch of siw_alloc_mr, and the freed mr->mem is used in siw_mr_drop_mem(mr). My patch moves "mr->mem = mem" behind the if (xa_alloc_cyclic(..)<0) {} section, to avoid the uaf.

CVSS metrics

4 scores · 4 sources · 1 version

EPSS trend

Probability

0.27%

Chance of exploitation in the next 30 days

Percentile

19%

Versus all other CVEs

30-day change

No change 0.00 pp

From 0.27% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: local access, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.

Ubuntu82 products
  • linux< 5.4.0-77.86
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-aws< 5.4.0-1051.53
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Linux2 products
  • linux≥ 2251334dcac9eb337575d8767e2a6a7e81848f7f, < 30b9e92d0b5e5d5dc1101ab856c17009537cbca4 | ≥ 2251334dcac9eb337575d8767e2a6a7e81848f7f, < 608a4b90ece039940e9425ee2b39c8beff27e00c | ≥ 2251334dcac9eb337575d8767e2a6a7e81848f7f, < 3e22b88e02c194f6c80867abfef5cc09383461f4 | ≥ 2251334dcac9eb337575d8767e2a6a7e81848f7f, < ad9ce7188432650469a6c7625bf479f5ed0b6155 | ≥ 2251334dcac9eb337575d8767e2a6a7e81848f7f, < 3093ee182f01689b89e9f8797b321603e5de4f63 | 5.3
  • linux_kernel≥ 5.3, < 5.4.119 | ≥ 5.5, < 5.10.37 | ≥ 5.11, < 5.11.21 | ≥ 5.12, < 5.12.4
Debian1 product
  • linux< 5.10.38-1

3 vendors · 85 products

References

9 links