In the Linux kernel, the following vulnerability has been resolved: hdlc_ppp: sync per-proto timers before freeing hdlc state Each PPP control protocol (LCP/IPCP/IPV6CP) embedded in struct ppp registers a timer via timer_setup(). That struct ppp is the hdlc->state allocation, which detach_hdlc_protocol() frees with kfree() in both teardown paths: unregister_hdlc_device() and the re-attach inside attach_hdlc_protocol(). The ppp proto never registered a .detach callback, so detach_hdlc_protocol() performs no timer synchronization before the kfree(). The only cancel, timer_delete(&proto->timer) in ppp_cp_event(), is partial (it does not wait for a running callback) and only runs on the ->CLOSED transition; ppp_stop()/ppp_close() do not sync either. A ppp_timer callback already executing (blocked on ppp->lock) survives the kfree and then dereferences proto->state / ppp->lock in freed memory, leading to a use-after-free. Fix this by adding a .detach helper that calls timer_shutdown_sync() on every per-proto timer. detach_hdlc_protocol() invokes proto->detach(dev) before kfree(hdlc->state), so timer_shutdown_sync() now runs on both free paths. timer_shutdown_sync() is used instead of timer_delete_sync() because the keepalive path re-arms the timer through add_timer()/mod_timer() and shutdown blocks any re-activation during teardown. Initialize the per-protocol timers in ppp_ioctl() when the protocol is attached, and remove the now-redundant timer_setup() from ppp_start(), so that the timers are initialized exactly once at attach time and ppp_timer_release() never operates on uninitialized timer_list structures. attach_hdlc_protocol() uses kmalloc() (not kzalloc), so struct ppp's protos[i].timer is uninitialized garbage until the first timer_setup(); without this init-at-attach, attaching the PPP protocol without ever bringing the device up would leave timer_shutdown_sync() operating on uninitialized memory in .detach. Moving the init out of ppp_start() (which only runs on NETDEV_UP) into the attach path makes the initialization unconditional and avoids initializing the same timer_list twice. This bug was found by static analysis.

The Unity Linux 20 host has a package installed that is affected by a vulnerability as referenced in the UTSA-2026-098901 advisory.

    In the Linux kernel, the following vulnerability has been resolved:

    hdlc_ppp: sync per-proto timers before freeing hdlc state

    Each PPP control protocol (LCP/IPCP/IPV6CP) embedded in struct ppp     registers a timer via timer_setup(). That struct ppp is the     hdlc->state allocation, which detach_hdlc_protocol() frees with kfree()     in both teardown paths: unregister_hdlc_device() and the re-attach inside     attach_hdlc_protocol().

    The ppp proto never registered a .detach callback, so     detach_hdlc_protocol() performs no timer synchronization before the     kfree(). The only cancel, timer_delete(&proto->timer) in ppp_cp_event(),     is partial (it does not wait for a running callback) and only runs on the
    ->CLOSED transition; ppp_stop()/ppp_close() do not sync either. A     ppp_timer callback already executing (blocked on ppp->lock) survives the     kfree and then dereferences proto->state / ppp->lock in freed memory,     leading to a use-after-free.

    Fix this by adding a .detach helper that calls timer_shutdown_sync() on     every per-proto timer. detach_hdlc_protocol() invokes proto->detach(dev)     before kfree(hdlc->state), so timer_shutdown_sync()     now runs on both free paths.
    timer_shutdown_sync() is used instead of timer_delete_sync() because the     keepalive path re-arms the timer through add_timer()/mod_timer() and     shutdown blocks any re-activation during teardown.

    Initialize the per-protocol timers in ppp_ioctl() when the protocol is     attached, and remove the now-redundant timer_setup() from ppp_start(), so     that the timers are initialized exactly once at attach time and     ppp_timer_release() never operates on uninitialized timer_list     structures. attach_hdlc_protocol() uses kmalloc() (not kzalloc), so     struct ppp's protos[i].timer is uninitialized garbage until the first     timer_setup(); without this init-at-attach, attaching the PPP protocol     without ever bringing the device up would leave timer_shutdown_sync()     operating on uninitialized memory in .detach. Moving the init out of     ppp_start() (which only runs on NETDEV_UP) into the attach path makes the     initialization unconditional and avoids initializing the same timer_list     twice.

    This bug was found by static analysis.

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.

An update of the linux package has been released.

The remote Debian 11 host has packages installed that are affected by multiple vulnerabilities as referenced in the dla-4717 advisory.

    - -------------------------------------------------------------------------     Debian LTS Advisory DLA-4717-1                debian-lts@lists.debian.org     https://www.debian.org/lts/security/               Emilio Pozuelo Monfort     August 05, 2026                               https://wiki.debian.org/LTS
    - -------------------------------------------------------------------------

    Package        : linux     Version        : 5.10.262-1     CVE ID         : CVE-2022-49803 CVE-2022-50114 CVE-2023-52494 CVE-2025-23131                      CVE-2025-39931 CVE-2026-23204 CVE-2026-31451 CVE-2026-31755                      CVE-2026-43216 CVE-2026-43219 CVE-2026-43499 CVE-2026-46116                      CVE-2026-46135 CVE-2026-46252 CVE-2026-46331 CVE-2026-52942                      CVE-2026-53138 CVE-2026-53157 CVE-2026-53158 CVE-2026-53159                      CVE-2026-53167 CVE-2026-53177 CVE-2026-53325 CVE-2026-53329                      CVE-2026-53332 CVE-2026-53381 CVE-2026-53382 CVE-2026-53385                      CVE-2026-53392 CVE-2026-53393 CVE-2026-53397 CVE-2026-53398                      CVE-2026-53399 CVE-2026-53400 CVE-2026-53402 CVE-2026-53403                      CVE-2026-63794 CVE-2026-63796 CVE-2026-63798 CVE-2026-63800                      CVE-2026-63801 CVE-2026-63803 CVE-2026-63806 CVE-2026-63808                      CVE-2026-63809 CVE-2026-63814 CVE-2026-63815 CVE-2026-63818                      CVE-2026-63822 CVE-2026-63823 CVE-2026-63824 CVE-2026-63827                      CVE-2026-63828 CVE-2026-63829 CVE-2026-63830 CVE-2026-63831                      CVE-2026-63834 CVE-2026-63835 CVE-2026-63836 CVE-2026-64188                      CVE-2026-64189 CVE-2026-64191 CVE-2026-64206 CVE-2026-64249                      CVE-2026-64252 CVE-2026-64266 CVE-2026-64268 CVE-2026-64271                      CVE-2026-64273 CVE-2026-64274 CVE-2026-64275 CVE-2026-64276                      CVE-2026-64277 CVE-2026-64296 CVE-2026-64298 CVE-2026-64299                      CVE-2026-64303 CVE-2026-64304 CVE-2026-64306 CVE-2026-64312                      CVE-2026-64313 CVE-2026-64315 CVE-2026-64316 CVE-2026-64317                      CVE-2026-64318 CVE-2026-64322 CVE-2026-64323 CVE-2026-64324                      CVE-2026-64329 CVE-2026-64330 CVE-2026-64331 CVE-2026-64332                      CVE-2026-64333 CVE-2026-64334 CVE-2026-64335 CVE-2026-64337                      CVE-2026-64338 CVE-2026-64340 CVE-2026-64342 CVE-2026-64343                      CVE-2026-64344 CVE-2026-64345 CVE-2026-64347 CVE-2026-64348                      CVE-2026-64351 CVE-2026-64359 CVE-2026-64360 CVE-2026-64361                      CVE-2026-64362 CVE-2026-64363 CVE-2026-64364 CVE-2026-64370                      CVE-2026-64371 CVE-2026-64372 CVE-2026-64373 CVE-2026-64374                      CVE-2026-64375 CVE-2026-64378 CVE-2026-64379 CVE-2026-64380                      CVE-2026-64381 CVE-2026-64403 CVE-2026-64406 CVE-2026-64408                      CVE-2026-64411 CVE-2026-64412 CVE-2026-64413 CVE-2026-64420                      CVE-2026-64422 CVE-2026-64423 CVE-2026-64425 CVE-2026-64429                      CVE-2026-64435 CVE-2026-64436 CVE-2026-64438 CVE-2026-64442                      CVE-2026-64445 CVE-2026-64446 CVE-2026-64448 CVE-2026-64450                      CVE-2026-64452 CVE-2026-64455 CVE-2026-64456 CVE-2026-64461                      CVE-2026-64462 CVE-2026-64465 CVE-2026-64468 CVE-2026-64469                      CVE-2026-64470 CVE-2026-64471 CVE-2026-64475 CVE-2026-64478                      CVE-2026-64483 CVE-2026-64484 CVE-2026-64487 CVE-2026-64488                      CVE-2026-64494 CVE-2026-64495 CVE-2026-64496 CVE-2026-64497                      CVE-2026-64500 CVE-2026-64503 CVE-2026-64504 CVE-2026-64505                      CVE-2026-64510 CVE-2026-64514 CVE-2026-64529 CVE-2026-64534                      CVE-2026-64538 CVE-2026-64540 CVE-2026-64541 CVE-2026-64544                      CVE-2026-64546 CVE-2026-64547 CVE-2026-64548 CVE-2026-64549                      CVE-2026-64550 CVE-2026-64551 CVE-2026-64553 CVE-2026-64554                      CVE-2026-64560

    Several vulnerabilities have been discovered in the Linux kernel that     may lead to a privilege escalation, denial of service or information     leaks.

    For Debian 11 bullseye, these problems have been fixed in version     5.10.262-1. This version additionally includes many more bug fixes     from stable updates 5.10.260-5.10.262.

    We recommend that you upgrade your linux packages.

    For the detailed security status of linux please refer to     its security tracker page at:
    https://security-tracker.debian.org/tracker/linux

    Further information about Debian LTS security advisories, how to apply     these updates to your system and frequently asked questions can be     found at: https://wiki.debian.org/LTS

Tenable has extracted the preceding description block directly from the Debian security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote Debian 11 host has packages installed that are affected by multiple vulnerabilities as referenced in the dla-4700 advisory.

    -------------------------------------------------------------------------     Debian LTS Advisory DLA-4700-1                debian-lts@lists.debian.org     https://www.debian.org/lts/security/                        Ben Hutchings     July 26, 2026                                 https://wiki.debian.org/LTS
    -------------------------------------------------------------------------

    Package        : linux-6.1     Version        : 6.1.177-1~deb11u1     CVE ID         : CVE-2025-23131 CVE-2026-23272 CVE-2026-23278 CVE-2026-23302                      CVE-2026-31451 CVE-2026-46252 CVE-2026-52928 CVE-2026-53138                      CVE-2026-53139 CVE-2026-53157 CVE-2026-53158 CVE-2026-53163                      CVE-2026-53167 CVE-2026-53325 CVE-2026-53327 CVE-2026-53359                      CVE-2026-53362 CVE-2026-53366 CVE-2026-53381 CVE-2026-53382                      CVE-2026-53383 CVE-2026-53384 CVE-2026-53385 CVE-2026-53388                      CVE-2026-53390 CVE-2026-53391 CVE-2026-53397 CVE-2026-53398                      CVE-2026-53403 CVE-2026-63794 CVE-2026-63795 CVE-2026-63796                      CVE-2026-63798 CVE-2026-63800 CVE-2026-63801 CVE-2026-63803                      CVE-2026-63807 CVE-2026-63808 CVE-2026-63809 CVE-2026-63814                      CVE-2026-63817 CVE-2026-63822 CVE-2026-63823 CVE-2026-63824                      CVE-2026-63827 CVE-2026-63828 CVE-2026-63830 CVE-2026-63831                      CVE-2026-63833 CVE-2026-63834 CVE-2026-63835 CVE-2026-63836                      CVE-2026-64188 CVE-2026-64191 CVE-2026-64246 CVE-2026-64249                      CVE-2026-64252 CVE-2026-64254 CVE-2026-64529     Debian Bug     : 1130365

    Several vulnerabilities have been discovered in the Linux kernel that     may lead to a privilege escalation, denial of service or information     leaks.

    For Debian 11 bullseye, these problems have been fixed in version     6.1.177-1~deb11u1.  This version additionally updates the Microsoft     Azure Network Adapter (mana) driver, and includes many more bug fixes     from stable update 6.1.177.

    We recommend that you upgrade your linux-6.1 packages.

    For the detailed security status of linux-6.1 please refer to     its security tracker page at:
    https://security-tracker.debian.org/tracker/linux-6.1

    Further information about Debian LTS security advisories, how to apply     these updates to your system and frequently asked questions can be     found at: https://wiki.debian.org/LTS     Attachment:
    signature.asc     Description: PGP signature

Tenable has extracted the preceding description block directly from the Debian security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - hdlc_ppp: sync per-proto timers before freeing hdlc state Each PPP control protocol (LCP/IPCP/IPV6CP)     embedded in struct ppp registers a timer via timer_setup(). That struct ppp is the hdlc->state allocation,     which detach_hdlc_protocol() frees with kfree() in both teardown paths: unregister_hdlc_device() and the     re-attach inside attach_hdlc_protocol(). The ppp proto never registered a .detach callback, so     detach_hdlc_protocol() performs no timer synchronization before the kfree(). The only cancel,     timer_delete(&proto->timer) in ppp_cp_event(), is partial (it does not wait for a running callback) and     only runs on the ->CLOSED transition; ppp_stop()/ppp_close() do not sync either. A ppp_timer callback     already executing (blocked on ppp->lock) survives the kfree and then dereferences proto->state / ppp->lock     in freed memory, leading to a use-after-free. Fix this by adding a .detach helper that calls     timer_shutdown_sync() on every per-proto timer. detach_hdlc_protocol() invokes proto->detach(dev) before     kfree(hdlc->state), so timer_shutdown_sync() now runs on both free paths. timer_shutdown_sync() is used     instead of timer_delete_sync() because the keepalive path re-arms the timer through     add_timer()/mod_timer() and shutdown blocks any re-activation during teardown. Initialize the per-protocol     timers in ppp_ioctl() when the protocol is attached, and remove the now-redundant timer_setup() from     ppp_start(), so that the timers are initialized exactly once at attach time and ppp_timer_release() never     operates on uninitialized timer_list structures. attach_hdlc_protocol() uses kmalloc() (not kzalloc), so     struct ppp's protos[i].timer is uninitialized garbage until the first timer_setup(); without this init-at-     attach, attaching the PPP protocol without ever bringing the device up would leave timer_shutdown_sync()     operating on uninitialized memory in .detach. Moving the init out of ppp_start() (which only runs on     NETDEV_UP) into the attach path makes the initialization unconditional and avoids initializing the same     timer_list twice. This bug was found by static analysis. (CVE-2026-63803)

Note that Nessus relies on the presence of the package as reported by the vendor.

ID	Name	Product	Family	Type	Severity
340478	Unity Linux 20.1050a Security Update: kernel (UTSA-2026-098901)	Nessus	Unity Linux Local Security Checks	Local	high
337224	Amazon Linux 2 : kernel, --advisory ALAS2KERNEL-5.10-2026-129 (ALASKERNEL-5.10-2026-129)	Nessus	Amazon Linux Local Security Checks	Local	medium
333954	Photon OS 5.0: Linux PHSA-2026-5.0-92-0916	Nessus	PhotonOS Local Security Checks	Local	high
333941	Photon OS 5.0: Linux PHSA-2026-5.0-92-0926	Nessus	PhotonOS Local Security Checks	Local	high
332715	Debian dla-4717 : ata-modules-5.10.0-43-armmp-di - security update	Nessus	Debian Local Security Checks	Local	high
330014	Debian dla-4700 : linux-config-6.1 - security update	Nessus	Debian Local Security Checks	Local	high
329326	Photon OS 5.0: Linux PHSA-2026-5.0-0926	Nessus	PhotonOS Local Security Checks	Local	high
327893	Linux Distros Unpatched Vulnerability : CVE-2026-63803	Nessus	Misc.	Local	high
326038	Photon OS 5.0: Linux PHSA-2026-5.0-0916	Nessus	PhotonOS Local Security Checks	Local	high

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