CVE-2021-31859 — Incorrect privileges in the MU55 FlexiSpooler service in YSoft SafeQ 6 6

Incorrect privileges in the MU55 FlexiSpooler service in YSoft SafeQ 6 6.0.55 allows local user privilege escalation by overwriting the executable file via an alternative data stream.

01What is this vulnerability?

Incorrect privileges in the MU55 FlexiSpooler service in YSoft SafeQ 6 6.0.55 allows local user privilege escalation by overwriting the executable file via an alternative data stream.

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: 2021-07-14T16:38:13.000Z
• Last modified: 2024-08-03T23:10:30.830Z

09References

• www.ysoft.com — https://www.ysoft.com/en
• www.ysoft.com — https://www.ysoft.com/en/legal/ysoft-safeq-flexispooler