CVE-2025-71097: Linux kernel · Memory Leak
Affects Linux kernelSource CVE Database V5
Not known to be exploited · fixed in ee4183501ea556dca31f5ffd8690aa9fd25b609f : update Linux kernel when convenient.
Data as of 26 Oct 2026, 13:07 UTC
Rated by Threat Radar · No CVSS score from NVD or the CNA
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 3% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- CISA SSVC
- Exploitation
- No evidence of active exploitation and no public proof of concept
- Automatable
- Attackers cannot reliably automate steps 1–4 of the kill chain
- Technical impact
- Limited control over the software or limited information exposure
CISA SSVC assessment, 2026-06-10.
- Patch
- Available – fixed in ee4183501ea556dca31f5ffd8690aa9fd25b609f, e3fc381320d04e4a74311e576a86cac49a16fc43, ac782f4e3bfcde145b8a7f8af31d9422d94d172a +4
Exploitation evidence
Disclosed: evidence found.
CVE published 13 Jan 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
Description
In the Linux kernel, the following vulnerability has been resolved: ipv4: Fix reference count leak when using error routes with nexthop objects When a nexthop object is deleted, it is marked as dead and then fib_table_flush() is called to flush all the routes that are using the dead nexthop. The current logic in fib_table_flush() is to only flush error routes (e.g., blackhole) when it is called as part of network namespace dismantle (i.e., with flush_all=true). Therefore, error routes are not flushed when their nexthop object is deleted: # ip link add name dummy1 up type dummy # ip nexthop add id 1 dev dummy1 # ip route add 198.51.100.1/32 nhid 1 # ip route add blackhole 198.51.100.2/32 nhid 1 # ip nexthop del id 1 # ip route show blackhole 198.51.100.2 nhid 1 dev dummy1 As such, they keep holding a reference on the nexthop object which in turn holds a reference on the nexthop device, resulting in a reference count leak: # ip link del dev dummy1 [ 70.516258] unregister_netdevice: waiting for dummy1 to become free. Usage count = 2 Fix by flushing error routes when their nexthop is marked as dead. IPv6 does not suffer from this problem.
References
- git.kernel.org/stable/c/5de7ad7e18356e39e8fbf7edd185a5faaf4f385a (opens in a new tab)
- git.kernel.org/stable/c/33ff5c207c873215e54e6176624ed57423cb7dea (opens in a new tab)
- git.kernel.org/stable/c/30386e090c49e803c0616a7147e43409c32a2b0e (opens in a new tab)
- git.kernel.org/stable/c/5979338c83012110ccd45cae6517591770bfe536 (opens in a new tab)
- git.kernel.org/stable/c/ee4183501ea556dca31f5ffd8690aa9fd25b609f (opens in a new tab)
- git.kernel.org/stable/c/e3fc381320d04e4a74311e576a86cac49a16fc43 (opens in a new tab)
- git.kernel.org/stable/c/ac782f4e3bfcde145b8a7f8af31d9422d94d172a (opens in a new tab)
- cert-portal.siemens.com/productcert/html/ssa-019113.html (opens in a new tab)
- cert-portal.siemens.com/productcert/html/ssa-457936.html (opens in a new tab)