Vulnerability · Published Oct 16, 2026 · Assigned by VulnCheck

CVE-2026-111687WeRSS (we-mp-rss) through 1.5.3 RCE via template Parameter in /rss Endpoint

Critical 9.8

In plain English

A critical-severity security flaw in we-mp-rss from rachelos. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 1.0% (higher than 63% of all known vulnerabilities).

Severity (CVSS 3.1)9.8Critical

Exploit odds (30 days)1.0%top 36.9% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

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.

Affected products (as reported)

Vendor	Product	Versions
rachelos	we-mp-rss	0 – through 1.5.3

Weakness: CWE-95 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

References

https://hackmd.io/@hieuPenguinnn/werss-rss-template-unauth-ssti-rce third-party-advisory
https://github.com/rachelos/we-mp-rss/blob/v1.5.3/core/lax/template_parser.py#L1150-L1166 technical-description
https://github.com/rachelos/we-mp-rss/blob/v1.5.3/apis/rss.py#L185-L198 technical-description
VulnCheck Advisory: WeRSS (we-mp-rss) through 1.5.3 RCE via template Parameter in /rss Endpoint third-party-advisory