TI-2026-81081 Aliases CVE-2026-116877 GHSA-2472-xm32-fr75

Resource exhaustion in Semantic MediaWiki via #set_recurring_event

HIGH 77CWE-770Published 2026-10-27 · Updated 2026-11-02

Key facts

Attack vector: Network
Privileges required: None
User interaction: None
Attack complexity: Low
Attack requirements: None
Impact type: Denial of service
Confidentiality · integrity · availability: None · None · High
Fix status: Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-770.

Summary

Semantic MediaWiki from 2.5.0 before 7.3.1 contains uncontrolled resource consumption (CWE-770) that lets low-privilege editors bypass the recurring event limit by supplying a large limit parameter. Saving pages that use #set_recurring_event without an end date creates thousands or millions of date subobjects. This exhausts CPU, memory and database resources. A public exploit is linked in the references.

Written with Claude Haiku 5.5 from the sources below · 2026-11-04

Description from the CNA

Semantic MediaWiki from 2.5.0 before 7.3.1 contains an uncontrolled resource consumption vulnerability that allows low-privilege editors to bypass smwgMaxNumRecurringEvents by supplying a large limit parameter. Attackers can save pages using #set_recurring_event without an end date to generate thousands or millions of date subobjects, exhausting CPU, memory, and database resources.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV

EPSS 0.00375 31st percentileScored 2026-11-07

Public exploit Yes 1 exploit referenceTagged by NVD

Fix Fixed SemanticMediaWiki (SemanticMediaWiki): 7.3.1

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: Poc
Automatable: Yes
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
SemanticMediaWiki	SemanticMediaWiki	2.5.0 to before 7.3.1	7.3.1	Patch available	CNA

SemanticMediaWiki VendorSemanticMediaWiki Affected 2.5.0 to before 7.3.1 Fixed in 7.3.1 Patch available CNA

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:a:semantic-mediawiki:semantic_mediawiki::::::mediawiki::*	2.5.0 to before 7.3.1	Vulnerable	SemanticMediaWiki

cpe:2.3:a:semantic-mediawiki:semantic_mediawiki:*:*:*:*:*:mediawiki:*:* Versions 2.5.0 to before 7.3.1 Vulnerable ·SemanticMediaWiki

Remediation

Upgrade Semantic MediaWiki to version 7.3.1, the fixed version.

Written with Claude Haiku 5.5 from the sources below · 2026-11-04

Fix · CNA SemanticMediaWiki (SemanticMediaWiki) Fixed in 7.3.1

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

Release · 2026-10-27
SemanticMediaWiki 7.3.1
20 records Highest priority Priority HIGH 4 HIGH, 13 MEDIUM, 3 LOW
Other records, highest priority first
- TI-2026-81076 Semantic MediaWiki search lets attackers exhaust CPU via long termsPriority HIGH 77
- TI-2026-81075 Uncontrolled recursion in Semantic MediaWiki via Special:AskPriority HIGH 77
- TI-2026-81077 Missing authorization in Semantic MediaWiki smwtask APIPriority HIGH 70
Show all 20 records →

Timeline

2026-10-27 Threatist record created from CVE-2026-116877
2026-10-27 Alias added: GHSA-2472-xm32-fr75
2026-10-28 Priority changed: MEDIUM → LOW
2026-11-02 CISA SSVC decision points changed
2026-11-02 Priority changed: LOW → HIGH

References

Exploit 1

GitHub Security Advisory (GHSA-vxrm-2g9f-2vqh)

Patch 1

https://github.com/SemanticMediaWiki/SemanticMediaWiki/commit/215599f0fc03274fd4cee9ba0f7162f5a38c031b

TI-2026-81076 Semantic MediaWiki search lets attackers exhaust CPU via long terms CVSS 4.0HIGH 8.7
TI-2026-81075 Uncontrolled recursion in Semantic MediaWiki via Special:Ask CVSS 4.0HIGH 8.7
TI-2026-81077 Missing authorization in Semantic MediaWiki smwtask API CVSS 4.0MEDIUM 6.9
TI-2026-81084 Cross-site request forgery in Semantic MediaWiki SMWAdmin page CVSS 4.0HIGH 7.1
TI-2026-81083 Missing authorization in Semantic MediaWiki smwtask update task CVSS 4.0MEDIUM 6.9
TI-2026-81080 Missing authorization in Semantic MediaWiki lets editors lock pages CVSS 4.0HIGH 7.1

See all 22 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences