Quick answers
- Is CVE-2026-116877 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-116877 being exploited in the wild.
- How severe is CVE-2026-116877?
- Medium severity, with a CVSS score of 6.5, published 27 October 2026.
- Which products and versions are affected?
- Semantic MediaWiki 2.5.0 to before 7.3.1.
- Is there a fix for CVE-2026-116877?
- Yes: fixed in 7.3.1. Until then: Disable the #set_recurring_event parser function or restrict page editing permissions to trusted administrators until an upgrade is applied. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-116877 attacked?
- It is attacked over the network, in a software library.
- Am I affected by CVE-2026-116877?
- Check whether you run Semantic MediaWiki at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
How to fix
- Fixed in: 7.3.1
Disable the #set_recurring_event parser function or restrict page editing permissions to trusted administrators until an upgrade is applied.
Technical details
The #set_recurring_event parser function accepts a caller-controlled limit parameter that bypasses the smwgMaxNumRecurringEvents safety limit when no end date is supplied. The RecurringEvents::parse() method overwrites the configured maximum with the user-supplied limit value without clamping, allowing attackers to generate far more date subobjects than intended. An authenticated editor (or any user if anonymous editing is enabled) can save or render a page containing this payload to force server-side computation proportional to the attacker-controlled count.
Affected products
- Semantic MediaWiki Semantic MediaWiki 2.5.0 to before 7.3.1
Timeline
- 2026-09-28: disclosed
- 2026-10-27: advisory