CVE-2020-36646 [Low] | Security Vulnerability in Zenlib

A vulnerability classified as problematic has been found in MediaArea ZenLib up to 0.4.38. This affects the function Ztring::Date_From_Seconds_1970_Local of the file Source/ZenLib/Ztring.cpp. The manipulation of the argument Value leads to unchecked return value to null pointer dereference. Upgrading to version 0.4.39 is able to address this issue. The identifier of the patch is 6475fcccd37c9cf17e0cfe263b5fe0e2e47a8408. It is recommended to upgrade the affected component. The identifier VDB-217629 was assigned to this vulnerability.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-05-03	0.10%	2.58%	+2.48%
2	2025-11-21	1.50%	0.10%	-1.41%
3	2025-11-18	—	1.50%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-05-03

0.10%

2.58%

+2.48%

2025-11-21

1.50%

0.10%

-1.41%

2025-11-18

—

1.50%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
3.5	3.1	LOW	`CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L` Click to expand Attack vector (AV:A) Attacker has to be nearby on the network—same office, same link, that vibe—not the whole wide internet. 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:L) A normal user session is enough; they don’t have to be admin. 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:L) Might cause slowdowns, glitches, or partial disruption—not a full brick.	2.1	1.4	[email protected]
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]
2.3	2.0	LOW	`AV:A/AC:M/Au:S/C:N/I:N/A:P` Click to expand Access vector (AV:A) Requires access to an adjacent network segment. Access complexity (AC:M) Exploitation needs some favorable conditions, but not exceptional ones. Authentication (AU:S) A single authentication is required. Confidentiality impact (C:N) No confidentiality impact. Integrity impact (I:N) No integrity impact. Availability impact (A:P) Partial availability impact.	4.4	2.9	[email protected]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

3.5

3.1

LOW

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

Attack vector (AV:A): Attacker has to be nearby on the network—same office, same link, that vibe—not the whole wide internet.
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:L): A normal user session is enough; they don’t have to be admin.
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:L): Might cause slowdowns, glitches, or partial disruption—not a full brick.

2.1

1.4

[email protected]

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]

2.3

2.0

LOW

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

Access vector (AV:A): Requires access to an adjacent network segment.
Access complexity (AC:M): Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:S): A single authentication is required.
Confidentiality impact (C:N): No confidentiality impact.
Integrity impact (I:N): No integrity impact.
Availability impact (A:P): Partial availability impact.

4.4

2.9

[email protected]

OS Trackers for CVE-2020-36646

vendor	priority	summary	link
`debian`	not yet assigned	CVE-2020-36646 not yet assigned priority: Debian including 1 source packages (libzen), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5.	https://security-tracker.debian.org/tracker/CVE-2020-36646
`ubuntu`	medium	CVE-2020-36646 medium priority: Ubuntu including 1 source packages (libzen), 8 status rows across 8 suites (bionic, focal, jammy, kinetic, lunar, trusty, upstream, xenial): released 5, not-affected 3.	https://ubuntu.com/security/CVE-2020-36646

Affected software / configurations for CVE-2020-36646

Vendor	Product	Version	Raw CPE
mediaarea	zenlib	>= 0.4.0, < 0.4.39	cpe:2.3:a:mediaarea:zenlib::::::::

References for CVE-2020-36646

URL	Tags
https://github.com/MediaArea/ZenLib/commit/6475fcccd37c9cf17e0cfe263b5fe0e2e47a8408	Patch
https://github.com/MediaArea/ZenLib/pull/119	Patch
https://github.com/MediaArea/ZenLib/releases/tag/v0.4.39	Release Notes
https://vuldb.com/?ctiid.217629	Third Party Advisory VDB Entry
https://vuldb.com/?id.217629	Third Party Advisory VDB Entry

URL

CVE-2020-36646 | MediaArea ZenLib Ztring.cpp Date_From_Seconds_1970_Local unknown vulnerability

Exploit prediction scoring system (EPSS) score for CVE-2020-36646

Common vulnerability scoring system (CVSS) metrics for CVE-2020-36646

Weakness enumeration for CVE-2020-36646

OS Trackers for CVE-2020-36646

Affected software / configurations for CVE-2020-36646

References for CVE-2020-36646