CVE-2020-29363 [High] | Out-of-bounds Write in P11-Kit

An issue was discovered in p11-kit 0.23.6 through 0.23.21. A heap-based buffer overflow has been discovered in the RPC protocol used by p11-kit server/remote commands and the client library. When the remote entity supplies a serialized byte array in a CK_ATTRIBUTE, the receiving entity may not allocate sufficient length for the buffer to store the deserialized value.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-04-19	0.57%	0.36%	-0.22%
2	2025-11-21	0.65%	0.57%	-0.08%
3	2025-11-18	—	0.65%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-04-19

0.57%

0.36%

-0.22%

2025-11-21

0.65%

0.57%

-0.08%

2025-11-18

—

0.65%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
7.5	3.1	HIGH	`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H` Click to expand Attack vector (AV:N) Could be attacked over the internet or any normal routed network—not just someone sitting at the machine. 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:N) No account or special rights needed—anonymous or random user is enough. 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:N) Doesn’t really leak secrets in a meaningful way. Integrity (I:N) Data isn’t meaningfully altered or forged. Availability (A:H) Could take the service down hard or make it unusable for people who depend on it.	3.9	3.6	[email protected]
5.0	2.0	MEDIUM	`AV:N/AC:L/Au:N/C:N/I:N/A:P` Click to expand Access vector (AV:N) Can be exploited remotely over network reachability. Access complexity (AC:L) Exploitation conditions are straightforward and predictable. Authentication (AU:N) No authentication is required. Confidentiality impact (C:N) No confidentiality impact. Integrity impact (I:N) No integrity impact. Availability impact (A:P) Partial availability impact.	10.0	2.9	[email protected]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

7.5

3.1

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand

Attack vector (AV:N): Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
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:N): No account or special rights needed—anonymous or random user is enough.
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:N): Doesn’t really leak secrets in a meaningful way.
Integrity (I:N): Data isn’t meaningfully altered or forged.
Availability (A:H): Could take the service down hard or make it unusable for people who depend on it.

3.9

3.6

[email protected]

5.0

2.0

MEDIUM

AV:N/AC:L/Au:N/C:N/I:N/A:P Click to expand

Access vector (AV:N): Can be exploited remotely over network reachability.
Access complexity (AC:L): Exploitation conditions are straightforward and predictable.
Authentication (AU:N): No authentication is required.
Confidentiality impact (C:N): No confidentiality impact.
Integrity impact (I:N): No integrity impact.
Availability impact (A:P): Partial availability impact.

10.0

2.9

[email protected]

OS Trackers for CVE-2020-29363

vendor	priority	summary	link
`alpine`	high	CVE-2020-29363: 1 source package rows (p11-kit); 10 state rows across 10 repos (3.10-main, 3.11-main, 3.12-main, 3.17-main, 3.18-main, 3.19-main, 3.20-main, 3.21-main, 3.22-main, edge-main); fixed 10, open 0.	https://security.alpinelinux.org/vuln/CVE-2020-29363
`debian`	not yet assigned	CVE-2020-29363 not yet assigned priority: Debian including 1 source packages (p11-kit), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5.	https://security-tracker.debian.org/tracker/CVE-2020-29363
`redhat`	medium	—	https://access.redhat.com/security/cve/CVE-2020-29363
`suse`	high	CVE-2020-29363 severity important: SUSE including 44 source package names (libp11-kit0, libp11-kit0-0.23.22-150400.1.10, …), 201 product×package rows across 41 product lines (HPE Helion OpenStack 8, SUSE Enterprise Storage 5, … (41 product lines)): Known Not Affected 144, Fixed 57.	https://www.suse.com/security/cve/CVE-2020-29363/
`ubuntu`	medium	CVE-2020-29363 medium priority: Ubuntu including 1 source packages (p11-kit), 7 status rows across 7 suites (bionic, focal, groovy, hirsute, trusty, upstream, xenial): released 5, not-affected 2.	https://ubuntu.com/security/CVE-2020-29363

Affected software / configurations for CVE-2020-29363

Vendor	Product	Version	Raw CPE
p11-kit_project	p11-kit	>= 0.23.6, < 0.23.22	cpe:2.3:a:p11-kit_project:p11-kit::::::::
debian	debian_linux	10.0	cpe:2.3:o:debian:debian_linux:10.0:::::::*
oracle	communications_cloud_native_core_policy	1.14.0	cpe:2.3:a:oracle:communications_cloud_native_core_policy:1.14.0:::::::*

References for CVE-2020-29363

URL	Tags
https://github.com/p11-glue/p11-kit/releases	Release Notes Third Party Advisory
https://github.com/p11-glue/p11-kit/security/advisories/GHSA-5j67-fw89-fp6x	Third Party Advisory
https://www.debian.org/security/2021/dsa-4822	Third Party Advisory
https://www.oracle.com/security-alerts/cpuapr2022.html	Patch Third Party Advisory

URL

CVE-2020-29363

Exploit prediction scoring system (EPSS) score for CVE-2020-29363

Common vulnerability scoring system (CVSS) metrics for CVE-2020-29363

Weakness enumeration for CVE-2020-29363

OS Trackers for CVE-2020-29363

Affected software / configurations for CVE-2020-29363

References for CVE-2020-29363