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  4. CVE 2026 126771 opstree rems through 100 stored xss via
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Back to active CVEs
Medium · CVSS 5.1CVE-2026-126771

OpsTree REMS through 1.0.0 Stored XSS via Attachment Upload and PreviewCVE-2026-126771

Answer in brief

CVE-2026-126771 records a Medium severity (CVSS 5.1) vulnerability in OpsTree REMS through 1.0.0 Stored XSS via Attachment Upload and Preview. The current sources do not mark it as known exploited. The current feed maps OpsTree Solutions/REMS (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Nov 11, 2026Updated Nov 11, 2026Source checked Nov 11, 2026First seen by HOL Nov 11, 2026Material review Nov 11, 2026
Upstream Advisory

Key facts

Risk
Medium · CVSS 5.1
Exploitation
Not marked as known exploited
Affected software
1 mapped package or product
Fix availability
Not reported

Why this deserves its current priority

CVSS is 5.1. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps OpsTree Solutions/REMS (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
PackageAffected rangeFixed version
OpsTree Solutions/REMSgeneric>=0 <=1.0.0Not reported

Recommended response

  1. 1Check inventory. Check lockfiles and deployed manifests for OpsTree Solutions/REMS.
  2. 2Review the reported fix. Monitor this advisory for an available fix and review any installs of the affected package.

Evidence timeline and material changes

  1. Published upstream

    Nov 11, 2026

    Evidence: source:cvelist:source_dates:source-dates:record

  2. Source modified

    Nov 11, 2026

    Evidence: source:cvelist:source_dates:source-dates:record

  3. First seen by HOL

    Nov 11, 2026

Sources and claim methodology

  • GitHub security advisorygist.github.com
  • Source referenceopstree.com
  • Source referencevulncheck.com
Upstream source description

OpsTree REMS through 1.0.0 contains a stored cross-site scripting vulnerability that allows authenticated attackers to inject scripts by uploading attachments with spoofed text/html Content-Type. Attackers can upload HTML files named like test.html.pdf that render in the REMS origin via Preview, executing JavaScript in victims' browsers.

Quoted source text, attributed separately from HOL analysis.

Related CVEs

  • OpsTree REMS through 1.0.0 Reporter Spoofing via /api/v1/incidentsSame opstree solutions/rems package
  • OpsTree REMS through 1.0.0 Prompt Injection via RCA Chat AssistantSame opstree solutions/rems package
  • OpsTree REMS through 1.0.0 Authentication Bypass via is_local_auth FlagSame opstree solutions/rems package
  • OpsTree REMS through 1.0.0 Missing Authentication via /api/v1/databases Governance APISame opstree solutions/rems package
  • OpsTree REMS through 1.0.0 SSRF via Database Test ConnectionSame opstree solutions/rems package
  • OpsTree REMS through 1.0.0 Comment Author Spoofing via Incident Comment APISame opstree solutions/rems package

Record context

Vulnerability class
XSS
EPSS
Not reported
CWE IDs
CWE-79
Source
CVE List V5
Source checked
Nov 11, 2026
References
3 linked sources
Open source record