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Echo: linux: security update to 6.1.170-1

high Tenable Cloud Security Plugin ID 463184

Description

There are packages installed that are affected by a vulnerability referenced in the following CVE:

 - In the Linux kernel, the following vulnerability has been resolved: drm/i915/gt: fix refcount underflow in
 intel_engine_park_heartbeat A use-after-free / refcount underflow is possible when the heartbeat worker
 and intel_engine_park_heartbeat() race to release the same engine->heartbeat.systole request. The
 heartbeat worker reads engine->heartbeat.systole and calls i915_request_put() on it when the request is
 complete, but clears the pointer in a separate, non-atomic step. Concurrently, a request retirement on
 another CPU can drop the engine wakeref to zero, triggering __engine_park() ->
 intel_engine_park_heartbeat(). If the heartbeat timer is pending at that point, cancel_delayed_work()
 returns true and intel_engine_park_heartbeat() reads the stale non-NULL systole pointer and calls
 i915_request_put() on it again, causing a refcount underflow: ``` <4> [487.221889] Workqueue:
 i915-unordered engine_retire [i915] <4> [487.222640] RIP: 0010:refcount_warn_saturate+0x68/0xb0 ... <4>
 [487.222707] Call Trace: <4> [487.222711] <TASK> <4> [487.222716]
 intel_engine_park_heartbeat.part.0+0x6f/0x80 [i915] <4> [487.223115] intel_engine_park_heartbeat+0x25/0x40
 [i915] <4> [487.223566] __engine_park+0xb9/0x650 [i915] <4> [487.223973]
 ____intel_wakeref_put_last+0x2e/0xb0 [i915] <4> [487.224408] __intel_wakeref_put_last+0x72/0x90 [i915] <4>
 [487.224797] intel_context_exit_engine+0x7c/0x80 [i915] <4> [487.225238] intel_context_exit+0xf1/0x1b0
 [i915] <4> [487.225695] i915_request_retire.part.0+0x1b9/0x530 [i915] <4> [487.226178]
 i915_request_retire+0x1c/0x40 [i915] <4> [487.226625] engine_retire+0x122/0x180 [i915] <4> [487.227037]
 process_one_work+0x239/0x760 <4> [487.227060] worker_thread+0x200/0x3f0 <4> [487.227068] ?
 __pfx_worker_thread+0x10/0x10 <4> [487.227075] kthread+0x10d/0x150 <4> [487.227083] ?
 __pfx_kthread+0x10/0x10 <4> [487.227092] ret_from_fork+0x3d4/0x480 <4> [487.227099] ?
 __pfx_kthread+0x10/0x10 <4> [487.227107] ret_from_fork_asm+0x1a/0x30 <4> [487.227141] </TASK> ``` Fix this
 by replacing the non-atomic pointer read + separate clear with xchg() in both racing paths. xchg() is a
 single indivisible hardware instruction that atomically reads the old pointer and writes NULL. This
 guarantees only one of the two concurrent callers obtains the non-NULL pointer and performs the put, the
 other gets NULL and skips it. (cherry picked from commit 13238dc0ee4f9ab8dafa2cca7295736191ae2f42)
 (CVE-2026-31656)

Solution

Update the linux library and its related packages to version 6.1.170-1 or later.

See Also

https://advisory.echohq.com/cve/CVE-2026-31656

Plugin Details

Severity: High

ID: 463184

Version: Revision 1.1

Type: Local

Published: 10/2/2026

Updated: 10/2/2026

Risk Information

VPR

Risk Factor: Medium

Score: 4.9

Percentile: 57.94

CVSS v2

Risk Factor: Medium

Base Score: 6.8

Temporal Score: 5

Vector: CVSS2#AV:L/AC:L/Au:S/C:C/I:C/A:C

CVSS Score Source: CVE-2026-31656

CVSS v3

Risk Factor: High

Base Score: 7.8

Temporal Score: 6.8

Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

Exploit Ease: No known exploits are available

Patch Publication Date: 5/1/2026

Vulnerability Publication Date: 4/23/2026

Reference Information

CVE: CVE-2026-31656