CVE-2023-27641: The REPORT (after z but before a) parameter in wa.exe in L-Soft LISTSERV 16.5 before 17 allows an attacker to

Q: How do I fix CVE-2023-27641?

listserv: upgrade to 17.0. Exact commands for each OS are on this page.

Q: Is CVE-2023-27641 being exploited?

CVE-2023-27641 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2023-27641 affect?

CVE-2023-27641 affects listserv. Severity is medium (CVSS 6.1). The REPORT (after z but before a) parameter in wa.exe in L-Soft LISTSERV 16.5 before 17 allows an attacker to conduct XSS attacks via a crafted URL.

Q: How urgent is CVE-2023-27641?

Priority 43/100. Public exploit reference

This month

MEDIUM 6.1UPGRADE

CVE-2023-27641 is a medium-severity flaw (CVSS 6.1) affecting listserv. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

The REPORT (after z but before a) parameter in wa.exe in L-Soft LISTSERV 16.5 before 17 allows an attacker to conduct XSS attacks via a crafted URL.

Why this priority

Public exploit reference

A fixed release or distro patch exists.

Risk facts

CVSS score	6.1 (Medium)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	Required
EPSS exploit chance	1.1% (top 35%)
CISA exploited list	No
Weakness	CWE-79
Published	2023-03-05
Last modified	2026-06-17

Publisher (CNA): MITRE · Vendor: lsoft

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2023-03-05 22:15 UTCPublished CVE record published
2026-06-17 05:45 UTCUpdated Record last modified

lsoft listserv UPGRADE

Affected: < 17.0

Fixed in: 17.0

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy listserv || rpm -q listserv || listserv --version

2. UPGRADE to 17.0 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade listserv

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade listserv

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

Public exploits and detection

Public code exists for this CVE. Treat unpatched systems as at risk, and only run PoCs in a lab.

Nuclei scan template: L-Soft LISTSERV 16.5 - Cross-Site Scripting

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2023-27641?

listserv: upgrade to 17.0. Exact commands for each OS are on this page.

Is CVE-2023-27641 being exploited?

CVE-2023-27641 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2023-27641 affect?

CVE-2023-27641 affects listserv. Severity is medium (CVSS 6.1). The REPORT (after z but before a) parameter in wa.exe in L-Soft LISTSERV 16.5 before 17 allows an attacker to conduct XSS attacks via a crafted URL.

How urgent is CVE-2023-27641?

Priority 43/100. Public exploit reference

Related CVEs

CVE-2022-40319 HIGH 7.5 DOWNGRADE The LISTSERV 17 web interface allows remote attackers to conduct Insecure Direct Object References (IDOR) atta
CVE-2022-39195 MEDIUM 6.1 DOWNGRADE A cross-site scripting (XSS) vulnerability in the LISTSERV 17 web interface allows remote attackers to inject

References

← Back to latest CVEs