Medium severity · published Sep 11, 2025
CVE-2025-39742
RDMA: hfi1: fix possible divide-by-zero in find_hw_thread_mask()
5.5
CVSS
0.2%
EPSS
No
On KEV
Description
In the Linux kernel, the following vulnerability has been resolved:
RDMA: hfi1: fix possible divide-by-zero in find_hw_thread_mask()
The function divides number of online CPUs by num_core_siblings, and
later checks the divider by zero. This implies a possibility to get
and divide-by-zero runtime error. Fix it by moving the check prior to
division. This also helps to save one indentation level.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 7% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
KE
Kernel · Linux
4.8 before 5.4.297; 5.5 before 5.10.241; 5.11 before 5.15.190; 5.16 before 6.1.149; 6.2 before 6.6.103; 6.7 before 6.12.43; +2 more · source: NVD
LI
Linux · Linux
b094a36f90975373c3a241839869217a65f17d81 before 9bba1a9994c523b44db64f63b564b4719ea2b7ef; b094a36f90975373c3a241839869217a65f17d81 before 1a7cf828ed861de5be1aff99e10f114b363c19d3; b094a36f90975373c3a241839869217a65f17d81 before 9d3211cb61a0773a2440d0a0698c1e6e7429f907; b094a36f90975373c3a241839869217a65f17d81 before 4b4317b0d758ff92ba96f4e448a8992a6fe607bf; b094a36f90975373c3a241839869217a65f17d81 before 89fdac333a17ed990b41565630ef4791782e02f5; b094a36f90975373c3a241839869217a65f17d81 before 9b05e91afe948ed819bf87d7ba0fccf451ed79a6; +4 more · source: vendor
DL
Debian Linux · Debian
11.0 · source: NVD
SC
SIMATIC CN 4100 · Siemens
before V5.0 · source: CISA
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-39742
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-39742
Patch
https://git.kernel.org/stable/c/1a7cf828ed861de5be1aff99e10f114b363c19d3
Patch
https://git.kernel.org/stable/c/31d0599a23efdbfe579bfbd1eb8f8c942f13744d
Patch
https://git.kernel.org/stable/c/4b4317b0d758ff92ba96f4e448a8992a6fe607bf
Patch
https://git.kernel.org/stable/c/59f7d2138591ef8f0e4e4ab5f1ab674e8181ad3a
Patch
https://git.kernel.org/stable/c/89fdac333a17ed990b41565630ef4791782e02f5
Patch
https://git.kernel.org/stable/c/9b05e91afe948ed819bf87d7ba0fccf451ed79a6
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