Debian Security Advisory
DLA-2557-1 linux-4.19 -- LTS security update
- Date Reported:
- 12 Feb 2021
- Affected Packages:
- Security database references:
- In the Debian bugtracking system: Bug 970736, Bug 972345, Bug 977048, Bug 977615.
In Mitre's CVE dictionary: CVE-2020-27815, CVE-2020-27825, CVE-2020-27830, CVE-2020-28374, CVE-2020-29568, CVE-2020-29569, CVE-2020-29660, CVE-2020-29661, CVE-2020-36158, CVE-2021-3347, CVE-2021-20177.
- More information:
Several vulnerabilities have been discovered in the Linux kernel that may lead to a privilege escalation, denial of service or information leaks.
A flaw was reported in the JFS filesystem code allowing a local attacker with the ability to set extended attributes to cause a denial of service.
pi3Zabrocki reported a use-after-free flaw in the ftrace ring buffer resizing logic due to a race condition, which could result in denial of service or information leak.
Shisong Qin reported a NULL pointer dereference flaw in the Speakup screen reader core driver.
David Disseldorp discovered that the LIO SCSI target implementation performed insufficient checking in certain XCOPY requests. An attacker with access to a LUN and knowledge of Unit Serial Number assignments can take advantage of this flaw to read and write to any LIO backstore, regardless of the SCSI transport settings.
- CVE-2020-29568 (XSA-349)
Michael Kurth and Pawel Wieczorkiewicz reported that frontends can trigger OOM in backends by updating a watched path.
- CVE-2020-29569 (XSA-350)
Olivier Benjamin and Pawel Wieczorkiewicz reported a use-after-free flaw which can be triggered by a block frontend in Linux blkback. A misbehaving guest can trigger a dom0 crash by continuously connecting / disconnecting a block frontend.
Jann Horn reported a locking inconsistency issue in the tty subsystem which may allow a local attacker to mount a read-after-free attack against TIOCGSID.
Jann Horn reported a locking issue in the tty subsystem which can result in a use-after-free. A local attacker can take advantage of this flaw for memory corruption or privilege escalation.
A buffer overflow flaw was discovered in the mwifiex WiFi driver which could result in denial of service or the execution of arbitrary code via a long SSID value.
It was discovered that PI futexes have a kernel stack use-after-free during fault handling. An unprivileged user could use this flaw to crash the kernel (resulting in denial of service) or for privilege escalation.
A flaw was discovered in the Linux implementation of string matching within a packet. A privileged user (with root or CAP_NET_ADMIN) can take advantage of this flaw to cause a kernel panic when inserting iptables rules.
For Debian 9 stretch, these problems have been fixed in version 4.19.171-2~deb9u1.
We recommend that you upgrade your linux-4.19 packages.
For the detailed security status of linux-4.19 please refer to its security tracker page at: https://security-tracker.debian.org/tracker/linux-4.19
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