PatchSiren

PatchSiren cyber security CVE debrief

CVE-2026-82880 yacy CVE debrief

YaCy Search Server through 1.941 contains an XML external entity injection vulnerability in SVG, FreeMind, and OpenSearch parsers that fail to disable external entity resolution. Attackers can publish malicious documents with DOCTYPE declarations containing SYSTEM entities pointing to local files, causing the crawler to exfiltrate file contents into the searchable index.

Vendor
yacy
Product
yacy_search_server
CVSS
HIGH 8.7
CISA KEV
Not listed in stored evidence
Original CVE published
2026-08-31
Original CVE updated
2026-08-31
Advisory published
2026-08-31
Advisory updated
2026-08-31

Who should care

Administrators and users of YaCy Search Server 1.941 or earlier, as well as organizations relying on this software for search functionality, should be aware of this vulnerability and take necessary precautions to mitigate potential risks.

Technical summary

The YaCy Search Server through 1.941 contains an XML external entity injection vulnerability due to the failure to disable external entity resolution in SVG, FreeMind, and OpenSearch parsers. This allows attackers to publish malicious documents with DOCTYPE declarations containing SYSTEM entities pointing to local files, potentially leading to file contents being exfiltrated into the searchable index.

Defensive priority

High priority due to high CVSS score of 8.7 and potential for sensitive file exfiltration.

Recommended defensive actions

  • Inventory and verify YaCy Search Server installations for version 1.941 or earlier.
  • Restrict access to the YaCy Search Server crawler and limit document publishing to trusted sources.
  • Implement compensating controls such as monitoring for suspicious crawler activity and potential file exfiltration.
  • Apply vendor patches or updates when available.
  • Consider disabling external entity resolution in SVG, FreeMind, and OpenSearch parsers as a temporary mitigation.

Evidence notes

Evidence from official CVE Program record and NIST NVD detail page supports the existence of the vulnerability in YaCy Search Server through 1.941. However, details about affected configurations and vendor remediation are limited.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-82880 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-82880

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2026-82880 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-82880

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.