CVE-2020-29660

Exp

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.

Published: 2020-12-09 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2020-29660 is rated Exploit Available (50/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.03%). 2 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2020-29660

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2020-29660

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-24 0.10% 0.03% -0.07%
2 2025-03-30 0.34% 0.10% -0.24%
3 2025-03-29 — 0.34% —

Full EPSS history (9 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2020-29660

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
4.4 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:H)
They need powerful rights—admin, root, or similar—before this pays off.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 0.8 3.6 [email protected]
2.1 2.0 LOW
AV:L/AC:L/Au:N/C:P/I:N/A:N Click to expand
Access vector (AV:L)
Requires local access to the target system.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:N)
No availability impact.
 3.9 2.9 [email protected]

Weakness enumeration for CVE-2020-29660

OS Trackers for CVE-2020-29660

vendor priority summary link
debian not yet assigned CVE-2020-29660 not yet assigned priority: Debian including 1 source packages (linux), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2020-29660
redhat medium — https://access.redhat.com/security/cve/CVE-2020-29660
suse high CVE-2020-29660 severity important: SUSE including 741 source package names (amazon/suse-sles-15-sp1-chost-byos-v20210304-hvm-ssd-x86_64, amazon/suse-sles-15-sp1-chost-byos-v20220127-hvm-ssd-x86_64, …), 1274 product×package rows across 117 product lines (HPE Helion OpenStack 8, Image SLES12-SP5-Azure-BYOS, … (117 product lines)): Fixed 1142, Known Affected 129, Known Not Affected 3. https://www.suse.com/security/cve/CVE-2020-29660/
ubuntu medium CVE-2020-29660 medium priority: Ubuntu including 169 source packages (linux, linux-allwinner, …), 2181 status rows across 16 suites (bionic, focal, groovy, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): DNE 1696, not-affected 232, released 214, ignored 38, needed 1. https://ubuntu.com/security/CVE-2020-29660

Affected software / configurations for CVE-2020-29660

Vendor Product Version Raw CPE
linux linux_kernel <= 5.9.13 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
fedoraproject fedora 32 cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:*
fedoraproject fedora 33 cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*
debian debian_linux 9.0 cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
debian debian_linux 10.0 cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
netapp active_iq_unified_manager — cpe:2.3:a:netapp:active_iq_unified_manager:-:*:*:*:*:vmware_vsphere:*:*
broadcom fabric_operating_system — cpe:2.3:o:broadcom:fabric_operating_system:-:*:*:*:*:*:*:*
netapp solidfire_baseboard_management_controller_firmware — cpe:2.3:o:netapp:solidfire_baseboard_management_controller_firmware:-:*:*:*:*:*:*:*
netapp h410c_firmware — cpe:2.3:o:netapp:h410c_firmware:-:*:*:*:*:*:*:*
netapp a700s_firmware — cpe:2.3:o:netapp:a700s_firmware:-:*:*:*:*:*:*:*
netapp 8300_firmware — cpe:2.3:o:netapp:8300_firmware:-:*:*:*:*:*:*:*
netapp 8700_firmware — cpe:2.3:o:netapp:8700_firmware:-:*:*:*:*:*:*:*
netapp a400_firmware — cpe:2.3:o:netapp:a400_firmware:-:*:*:*:*:*:*:*

References for CVE-2020-29660

URL Tags
http://packetstormsecurity.com/files/164950/Kernel-Live-Patch-Security-Notice-LSN-0082-1.html Exploit Third Party Advisory VDB Entry
http://www.openwall.com/lists/oss-security/2020/12/10/1 Mailing List Patch Third Party Advisory
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=c8bcd9c5be24fb9e6132e97da5a35e55a83e36b9 Exploit Patch Vendor Advisory
https://lists.debian.org/debian-lts-announce/2021/02/msg00018.html Mailing List Third Party Advisory
https://lists.debian.org/debian-lts-announce/2021/03/msg00010.html Mailing List Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BOB25SU6XUL4TNP7KB63WNZSYTIYFDPP/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MZ7OAKAEFAXQRGBZK4LYUWINCD3D2XCL/
https://security.netapp.com/advisory/ntap-20210122-0001/ Third Party Advisory
https://www.debian.org/security/2021/dsa-4843 Third Party Advisory
cvelogic Threat Intelligence