A linux-4.19 security update has been released for Debian GNU/Linux 8 and 9 Extended LTS to address several vulnerabilities.

ELA-696-1 linux-4.19 security update

Package linux-4.19
Version 4.19.260-1~deb8u1 (jessie), 4.19.260-1~deb9u1 (stretch)
Related CVEs CVE-2021-4159 CVE-2021-33655 CVE-2021-33656 CVE-2022-1462 CVE-2022-1679 CVE-2022-2153 CVE-2022-2318 CVE-2022-2586 CVE-2022-2588 CVE-2022-2663 CVE-2022-3028 CVE-2022-26365 CVE-2022-26373 CVE-2022-33740 CVE-2022-33741 CVE-2022-33742 CVE-2022-33744 CVE-2022-36879 CVE-2022-36946 CVE-2022-39188 CVE-2022-39842 CVE-2022-40307

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

CVE-2021-4159

A flaw was found in the eBPF verifier which could lead to an
out-of-bounds read. If unprivileged use of eBPF is enabled, this
could leak sensitive information. This was already disabled by
default, which would fully mitigate the vulnerability.

CVE-2021-33655

A user with access to a framebuffer console device could cause a
memory out-of-bounds write via the FBIOPUT_VSCREENINFO ioctl.

CVE-2021-33656

A user with access to a framebuffer console device could cause a
memory out-of-bounds write via some font setting ioctls. These
obsolete ioctls have been removed.

CVE-2022-1462

一只狗 reported a race condition in the pty (pseudo-terminal)
subsystem that can lead to a slab out-of-bounds write. A local
user could exploit this to cause a denial of service (crash or
memory corruption) or possibly for privilege escalation.

CVE-2022-1679

The syzbot tool found a race condition in the ath9k_htc driver
which can lead to a use-after-free. This might be exploitable to
cause a denial service (crash or memory corruption) or possibly
for privilege escalation.

CVE-2022-2153

"kangel" reported a flaw in the KVM implementation for x86
processors which could lead to a null pointer dereference. A local
user permitted to access /dev/kvm could exploit this to cause a
denial of service (crash).

CVE-2022-2318

A use-after-free in the Amateur Radio X.25 PLP (Rose) support may
result in denial of service.

CVE-2022-2586

A use-after-free in the Netfilter subsystem may result in local
privilege escalation for a user with the CAP_NET_ADMIN capability
in any user or network namespace.

CVE-2022-2588

Zhenpeng Lin discovered a use-after-free flaw in the cls_route
filter implementation which may result in local privilege
escalation for a user with the CAP_NET_ADMIN capability in any
user or network namespace.

CVE-2022-2663

David Leadbeater reported flaws in the nf_conntrack_irc
connection-tracking protocol module. When this module is enabled
on a firewall, an external user on the same IRC network as an
internal user could exploit its lax parsing to open arbitrary TCP
ports in the firewall, to reveal their public IP address, or to
block their IRC connection at the firewall.

CVE-2022-3028

Abhishek Shah reported a race condition in the AF_KEY subsystem,
which could lead to an out-of-bounds write or read. A local user
could exploit this to cause a denial of service (crash or memory
corruption), to obtain sensitive information, or possibly for
privilege escalation.

CVE-2022-26365, CVE-2022-33740, CVE-2022-33741, CVE-2022-33742

Roger Pau Monne discovered that Xen block and network PV device
frontends don't zero out memory regions before sharing them with
the backend, which may result in information disclosure.
Additionally it was discovered that the granularity of the grant
table doesn't permit sharing less than a 4k page, which may also
result in information disclosure.

CVE-2022-26373

It was discovered that on certain processors with Intel's Enhanced
Indirect Branch Restricted Speculation (eIBRS) capabilities there
are exceptions to the documented properties in some situations,
which may result in information disclosure.

Intel's explanation of the issue can be found at
https://www.intel.com/content/www/us/en/developer/articles/technical/software-security-guidance/advisory-guidance/post-barrier-return-stack-buffer-predictions.html

CVE-2022-33744

Oleksandr Tyshchenko discovered that ARM Xen guests can cause a
denial of service to the Dom0 via paravirtual devices.

CVE-2022-36879

A flaw was discovered in xfrm_expand_policies in the xfrm
subsystem which can cause a reference count to be dropped twice.

CVE-2022-36946

Domingo Dirutigliano and Nicola Guerrera reported a memory
corruption flaw in the Netfilter subsystem which may result in
denial of service.

CVE-2022-39188

Jann Horn reported a race condition in the kernel's handling of
unmapping of certain memory ranges. When a driver created a
memory mapping with the VM_PFNMAP flag, which many GPU drivers do,
the memory mapping could be removed and freed before it was
flushed from the CPU TLBs. This could result in a page use-after-
free. A local user with access to such a device could exploit
this to cause a denial of service (crash or memory corruption) or
possibly for privilege escalation.

CVE-2022-39842

An integer overflow was discovered in the pxa3xx-gcu video driver
which could lead to a heap out-of-bounds write.

This driver is not enabled in Debian's official kernel
configurations.

CVE-2022-40307

A race condition was discovered in the EFI capsule-loader driver,
which could lead to use-after-free. A local user permitted to
access this device (/dev/efi_capsule_loader) could exploit this to
cause a denial of service (crash or memory corruption) or possibly
for privilege escalation. However, this device is normally only
accessible by the root user.
For Debian 8 jessie, these problems have been fixed in version 4.19.260-1~deb8u1.

For Debian 9 stretch, these problems have been fixed in version 4.19.260-1~deb9u1.

We recommend that you upgrade your linux-4.19 packages.

Further information about Extended LTS security advisories can be found at: https://deb.freexian.com/extended-lts/

  ELA-696-1 linux-4.19 security update