CVE-2019-20838 [High] | Out-of-bounds Read in Pcre

CVE-2019-20838 is rated Moderate Risk (46.1/100): CVSS High severity, with low exploitation likelihood (EPSS 0.23%). Review affected assets and schedule remediation.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-05-28	0.31%	0.23%	-0.07%
2	2025-11-21	1.23%	0.31%	-0.92%
3	2025-11-18	—	1.23%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-05-28

0.31%

0.23%

-0.07%

2025-11-21

1.23%

0.31%

-0.92%

2025-11-18

—

1.23%

—

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]
4.3	2.0	MEDIUM	`AV:N/AC:M/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:M) Exploitation needs some favorable conditions, but not exceptional ones. 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.	8.6	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]

4.3

2.0

MEDIUM

AV:N/AC:M/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:M): Exploitation needs some favorable conditions, but not exceptional ones.
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.

8.6

2.9

[email protected]

OS Trackers for CVE-2019-20838

vendor	priority	summary	link
`alpine`	—	CVE-2019-20838: 1 source package rows (pcre); 10 state rows across 5 repos (3.19-main, 3.20-main, 3.21-main, 3.22-main, edge-main); fixed 0, open 10.	https://security.alpinelinux.org/vuln/CVE-2019-20838
`debian`	unimportant	CVE-2019-20838 unimportant priority: Debian including 1 source packages (pcre3), 2 status rows across 2 suites (bookworm, bullseye): open 2.	https://security-tracker.debian.org/tracker/CVE-2019-20838
`redhat`	low	—	https://access.redhat.com/security/cve/CVE-2019-20838
`suse`	high	CVE-2019-20838 severity important: SUSE including 501 source package names (0.0.17-1.1:libpcre1-8.45-20.10.1, 0.1.0:libpcre1-8.45-20.10.1, …), 1210 product×package rows across 567 product lines (Container bci/bci-base-fips, Container bci/bci-busybox, … (567 product lines)): Fixed 1050, Known Affected 157, Known Not Affected 3.	https://www.suse.com/security/cve/CVE-2019-20838/
`ubuntu`	low	CVE-2019-20838 low priority: Ubuntu including 1 source packages (pcre3), 17 status rows across 17 suites (bionic, eoan, focal, groovy, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): ignored 8, released 5, needed 2, not-affected 2.	https://ubuntu.com/security/CVE-2019-20838

Affected software / configurations for CVE-2019-20838

Vendor	Product	Version	Raw CPE
pcre	pcre	< 8.43	cpe:2.3:a:pcre:pcre::::::::
apple	macos	< 11.0.1	cpe:2.3:o:apple:macos::::::::
splunk	universal_forwarder	>= 8.2.0, < 8.2.12	cpe:2.3:a:splunk:universal_forwarder::::::::
splunk	universal_forwarder	>= 9.0.0, < 9.0.6	cpe:2.3:a:splunk:universal_forwarder::::::::
splunk	universal_forwarder	9.1.0	cpe:2.3:a:splunk:universal_forwarder:9.1.0:::::::*

References for CVE-2019-20838

URL	Tags
http://seclists.org/fulldisclosure/2020/Dec/32	Mailing List Third Party Advisory
http://seclists.org/fulldisclosure/2021/Feb/14	Mailing List Third Party Advisory
https://bugs.gentoo.org/717920	Issue Tracking Patch Third Party Advisory VDB Entry
https://lists.apache.org/thread.html/rf9fa47ab66495c78bb4120b0754dd9531ca2ff0430f6685ac9b07772%40%3Cdev.mina.apache.org%3E	Mailing List Third Party Advisory
https://support.apple.com/kb/HT211931	Vendor Advisory
https://support.apple.com/kb/HT212147	Vendor Advisory
https://www.pcre.org/original/changelog.txt	Release Notes Vendor Advisory

URL

CVE-2019-20838

Exploit prediction scoring system (EPSS) score for CVE-2019-20838

Common vulnerability scoring system (CVSS) metrics for CVE-2019-20838

Weakness enumeration for CVE-2019-20838

OS Trackers for CVE-2019-20838

Affected software / configurations for CVE-2019-20838

References for CVE-2019-20838