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Unity Linux 20.1070e Security Update: kernel (UTSA-2025-987615)
medium Nessus Plugin ID 271038
Synopsis
The Unity Linux host is missing one or more security updates.Description
The Unity Linux 20 host has a package installed that is affected by a vulnerability as referenced in the UTSA-2025-987615 advisory.In the Linux kernel, the following vulnerability has been resolved:
net: openvswitch: fix leak of nested actions
While parsing user-provided actions, openvswitch module may dynamically allocate memory and store pointers in the internal copy of the actions.
So this memory has to be freed while destroying the actions.
Currently there are only two such actions: ct() and set(). However, there are many actions that can hold nested lists of actions and ovs_nla_free_flow_actions() just jumps over them leaking the memory.
For example, removal of the flow with the following actions will lead to a leak of the memory allocated by nf_ct_tmpl_alloc():
actions:clone(ct(commit),0)
Non-freed set() action may also leak the 'dst' structure for the tunnel info including device references.
Under certain conditions with a high rate of flow rotation that may cause significant memory leak problem (2MB per second in reporter's case). The problem is also hard to mitigate, because the user doesn't have direct control over the datapath flows generated by OVS.
Fix that by iterating over all the nested actions and freeing everything that needs to be freed recursively.
New build time assertion should protect us from this problem if new actions will be added in the future.
Unfortunately, openvswitch module doesn't use NLA_F_NESTED, so all attributes has to be explicitly checked. sample() and clone() actions are mixing extra attributes into the user-provided action list. That prevents some code generalization too.
Tenable has extracted the preceding description block directly from the Unity Linux security advisory.
Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.
Solution
Update the affected kernel package.See Also
http://www.nessus.org/u?d7469520
Plugin Details
Severity: Medium
ID: 271038
File Name: unity_linux_UTSA-2025-987615.nasl
Version: 1.1
Type: local
Published: 10/21/2025
Updated: 10/21/2025
Supported Sensors: Nessus
Risk Information
VPR
Risk Factor: Medium
Score: 4.4
CVSS v2
Risk Factor: Medium
Base Score: 4.6
Temporal Score: 3.4
Vector: CVSS2#AV:L/AC:L/Au:S/C:N/I:N/A:C
CVSS Score Source: CVE-2022-49086
CVSS v3
Risk Factor: Medium
Base Score: 5.5
Temporal Score: 4.8
Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C
Vulnerability Information
Required KB Items: Host/local_checks_enabled, Host/cpu, Host/UOS-Server/release, Host/UOS-Server/rpm-list
Exploit Ease: No known exploits are available
Patch Publication Date: 10/15/2025
Vulnerability Publication Date: 11/8/2022
Reference Information
CVE: CVE-2022-49086