SECURELYN

CVE-2026-111687

WeRSS (we-mp-rss) through 1.5.3 contains a remote code execution vulnerability that allows unauthenticated attackers to run code via the template parameter of the public GET /rss/{feed_id} endpoint. Attackers can supply a non-built-in ext value and a {{=expression}} template whose object-subclass traversal bypasses the eval denylist to run OS commands as the service account.

Scores

9.3
CVSS 9.3 out of 10, critical severity.
1%
EPSS 1% chance of exploitation in the next 30 days.

The facts

Published
16 October 2026
Last changed
16 October 2026
NVD status
Deferred
Severity
Critical, CVSS 9.3 out of 10 (version 4.0)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R…
Weakness
Known exploited
Not in the CISA Known Exploited Vulnerabilities catalogue in this build.
EPSS
1.0% chance of exploitation activity in the next 30 days (percentile 62).

Is there a Securelyn advisory?

Not yet. Securelyn writes plain-English advisories for the flaws that matter most to businesses. Subscribe to the digest to hear about them.

References