CVE-2023-27641 — The REPORT (after z but before a) parameter in wa

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.

01What is this vulnerability?

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.

02Affected products

Vendor	Product	Versions
n	a / n/a	n/a

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2023-03-05T00:00:00.000Z
• Last modified: 2025-03-06T15:53:06.972Z

09References

• github.com — https://github.com/hosakauk/exploits/blob/master/listserv_report_xss.MD