CVE-2018-18898 [High] | Denial of Service in Request Tracker

CVE-2018-18898 is rated Moderate Risk (59.5/100): CVSS High severity, with medium exploitation likelihood (EPSS 2.36%). Review affected assets and schedule remediation.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-06-15	1.37%	2.36%	+0.98%
2	2026-05-29	1.56%	1.37%	-0.18%
3	2026-05-26	—	1.56%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-06-15

1.37%

2.36%

+0.98%

2026-05-29

1.56%

1.37%

-0.18%

2026-05-26

—

1.56%

—

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-2018-18898

vendor	priority	summary	link
`alpine`	high	CVE-2018-18898: 1 source package rows (perl-email-address-list); 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-2018-18898
`debian`	not yet assigned	CVE-2018-18898 not yet assigned priority: Debian including 1 source packages (libemail-address-list-perl), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5.	https://security-tracker.debian.org/tracker/CVE-2018-18898
`ubuntu`	medium	CVE-2018-18898 medium priority: Ubuntu including 1 source packages (libemail-address-list-perl), 8 status rows across 8 suites (bionic, cosmic, disco, eoan, focal, trusty, upstream, xenial): released 6, DNE 1, ignored 1.	https://ubuntu.com/security/CVE-2018-18898

Affected software / configurations for CVE-2018-18898

Vendor	Product	Version	Raw CPE
bestpractical	request_tracker	>= 4.1.13, <= 4.4.0	cpe:2.3:a:bestpractical:request_tracker::::::::
fedoraproject	fedora	28	cpe:2.3:o:fedoraproject:fedora:28:::::::*
fedoraproject	fedora	29	cpe:2.3:o:fedoraproject:fedora:29:::::::*
canonical	ubuntu_linux	16.04	cpe:2.3:o:canonical:ubuntu_linux:16.04::::esm:::
canonical	ubuntu_linux	18.04	cpe:2.3:o:canonical:ubuntu_linux:18.04::::lts:::
debian	debian_linux	8.0	cpe:2.3:o:debian:debian_linux:8.0:::::::*
debian	debian_linux	10.0	cpe:2.3:o:debian:debian_linux:10.0:::::::*

References for CVE-2018-18898

URL	Tags
https://bestpractical.com/download-page	Product Release Notes
https://lists.debian.org/debian-lts-announce/2020/02/msg00009.html	Mailing List Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CPJVDT77ZPRU5Z2BEMZM7EBY6WZHUATZ/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/YR46PPHBEM76DNN4DEQMAYIKLCO3TQU2/
https://usn.ubuntu.com/4517-1/	Third Party Advisory

URL

CVE-2018-18898

Exploit prediction scoring system (EPSS) score for CVE-2018-18898

Common vulnerability scoring system (CVSS) metrics for CVE-2018-18898

Weakness enumeration for CVE-2018-18898

OS Trackers for CVE-2018-18898

Affected software / configurations for CVE-2018-18898

References for CVE-2018-18898