CVE-2020-29660

kernel: locking inconsistency in drivers/tty/tty_io.c and drivers/tty/tty_jobctrl.c can lead to a read-after-free

Severity Score

4.4

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

*SSVC

Descriptions

A locking inconsistency issue was discovered in the tty subsystem of the Linux kernel through 5.9.13. drivers/tty/tty_io.c and drivers/tty/tty_jobctrl.c may allow a read-after-free attack against TIOCGSID, aka CID-c8bcd9c5be24.

Se detectó un problema de inconsistencia de bloqueo en el subsistema tty del kernel de Linux versiones hasta 5.9.13. Los archivos drivers/tty/tty_io.c y drivers/tty/tty_jobctrl.c pueden permitir un ataque de lectura de la memoria previamente liberada contra TIOCGSID, también se conoce como CID-c8bcd9c5be24

A locking inconsistency issue was discovered in the tty subsystem of the Linux kernel. A local user could use this flaw to read numerical value from memory after free.

Daniele Antonioli, Nils Ole Tippenhauer, and Kasper Rasmussen discovered that legacy pairing and secure-connections pairing authentication in the Bluetooth protocol could allow an unauthenticated user to complete authentication without pairing credentials via adjacent access. A physically proximate attacker could use this to impersonate a previously paired Bluetooth device. Jay Shin discovered that the ext4 file system implementation in the Linux kernel did not properly handle directory access with broken indexing, leading to an out-of-bounds read vulnerability. A local attacker could use this to cause a denial of service. Various other issues were also addressed.

*Credits: N/A

Attack Vector

Local

Attack Complexity

Low

Privileges Required

High

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

None

Availability

None

Attack Vector

Local

Attack Complexity

Low

Authentication

None

Confidentiality

Partial

Integrity

None

Availability

None

* Common Vulnerability Scoring System

SSVC

Decision:-

Exploitation

Automatable

Tech. Impact

* Organization's Worst-case Scenario

Timeline

2020-12-09 CVE Reserved
2020-12-09 CVE Published
2024-08-04 CVE Updated
2024-08-04 First Exploit
2025-03-30 EPSS Updated
---------- Exploited in Wild
---------- KEV Due Date

CWE

CWE-416: Use After Free
CWE-667: Improper Locking

CAPEC

References (11)

URL	Tag	Source
https://lists.debian.org/debian-lts-announce/2021/02/msg00018.html	Mailing List
https://lists.debian.org/debian-lts-announce/2021/03/msg00010.html	Mailing List
https://security.netapp.com/advisory/ntap-20210122-0001	Third Party Advisory

URL	Date	SRC
http://packetstormsecurity.com/files/164950/Kernel-Live-Patch-Security-Notice-LSN-0082-1.html	2024-08-04
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=c8bcd9c5be24fb9e6132e97da5a35e55a83e36b9	2024-08-04

URL	Date	SRC
http://www.openwall.com/lists/oss-security/2020/12/10/1	2023-11-07

URL	Date	SRC
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BOB25SU6XUL4TNP7KB63WNZSYTIYFDPP	2023-11-07
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MZ7OAKAEFAXQRGBZK4LYUWINCD3D2XCL	2023-11-07
https://www.debian.org/security/2021/dsa-4843	2023-11-07
https://access.redhat.com/security/cve/CVE-2020-29660	2021-11-09
https://bugzilla.redhat.com/show_bug.cgi?id=1906522	2021-11-09

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Netapp Search vendor "Netapp"	Solidfire Baseboard Management Controller Firmware Search vendor "Netapp" for product "Solidfire Baseboard Management Controller Firmware"	-	-	Affected	in	Netapp Search vendor "Netapp"	Solidfire Baseboard Management Controller Search vendor "Netapp" for product "Solidfire Baseboard Management Controller"	-	-	Safe
Netapp Search vendor "Netapp"	H410c Firmware Search vendor "Netapp" for product "H410c Firmware"	-	-	Affected	in	Netapp Search vendor "Netapp"	H410c Search vendor "Netapp" for product "H410c"	-	-	Safe
Netapp Search vendor "Netapp"	A700s Firmware Search vendor "Netapp" for product "A700s Firmware"	-	-	Affected	in	Netapp Search vendor "Netapp"	A700s Search vendor "Netapp" for product "A700s"	-	-	Safe
Netapp Search vendor "Netapp"	8300 Firmware Search vendor "Netapp" for product "8300 Firmware"	-	-	Affected	in	Netapp Search vendor "Netapp"	8300 Search vendor "Netapp" for product "8300"	-	-	Safe
Netapp Search vendor "Netapp"	8700 Firmware Search vendor "Netapp" for product "8700 Firmware"	-	-	Affected	in	Netapp Search vendor "Netapp"	8700 Search vendor "Netapp" for product "8700"	-	-	Safe
Netapp Search vendor "Netapp"	A400 Firmware Search vendor "Netapp" for product "A400 Firmware"	-	-	Affected	in	Netapp Search vendor "Netapp"	A400 Search vendor "Netapp" for product "A400"	-	-	Safe
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				<= 5.9.13 Search vendor "Linux" for product "Linux Kernel" and version " <= 5.9.13"		-		Affected
Fedoraproject Search vendor "Fedoraproject"		Fedora Search vendor "Fedoraproject" for product "Fedora"				32 Search vendor "Fedoraproject" for product "Fedora" and version "32"		-		Affected
Fedoraproject Search vendor "Fedoraproject"		Fedora Search vendor "Fedoraproject" for product "Fedora"				33 Search vendor "Fedoraproject" for product "Fedora" and version "33"		-		Affected
Debian Search vendor "Debian"		Debian Linux Search vendor "Debian" for product "Debian Linux"				9.0 Search vendor "Debian" for product "Debian Linux" and version "9.0"		-		Affected
Debian Search vendor "Debian"		Debian Linux Search vendor "Debian" for product "Debian Linux"				10.0 Search vendor "Debian" for product "Debian Linux" and version "10.0"		-		Affected
Netapp Search vendor "Netapp"		Active Iq Unified Manager Search vendor "Netapp" for product "Active Iq Unified Manager"				-		vmware_vsphere		Affected
Broadcom Search vendor "Broadcom"		Fabric Operating System Search vendor "Broadcom" for product "Fabric Operating System"				-		-		Affected