TI-2026-81082 Aliases CVE-2026-116878 GHSA-xjgm-6w2q-3jqg

Resource exhaustion in Semantic MediaWiki via PropertyLabelSimilarity

MEDIUM 44CWE-400Published 2026-10-27 · Updated 2026-10-27

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-400.

Summary

Semantic MediaWiki from 2.5.0 before 7.3.1 contains uncontrolled resource consumption (CWE-400). A zero limit on Special:PropertyLabelSimilarity removes the SQL limit, so the page performs quadratic pairwise comparisons. An unauthenticated remote attacker can send repeated requests to exhaust PHP CPU, memory and database connections. An 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 anonymous attackers to force quadratic computation by supplying a zero limit to Special:PropertyLabelSimilarity. Attackers can send repeated requests with limit=0 to bypass the SQL LIMIT and trigger pairwise similar_text() comparisons, exhausting PHP CPU, memory, and database connections.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00407 35th 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: None
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-2026-81081 Resource exhaustion in Semantic MediaWiki via #set_recurring_eventPriority HIGH 77
- 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
Show all 20 records →

Timeline

2026-10-27 Threatist record created from CVE-2026-116878
2026-10-27 CISA SSVC decision points changed
2026-10-27 Alias added: GHSA-xjgm-6w2q-3jqg

References

Exploit 1

GitHub Security Advisory (GHSA-wh64-r5x2-vjgf)

Patch 1

https://github.com/SemanticMediaWiki/SemanticMediaWiki/commit/15ed8489a4ca142ea5417d0c4403dbbe0a3ee3f5

TI-2026-81081 Resource exhaustion in Semantic MediaWiki via #set_recurring_event CVSS 4.0HIGH 8.7
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

See all 22 →

Sources

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