CVE-2026-52891

CRITICALPre-NVD 9.99.9
EchelonGraph scoreMEDIUM confidence

This critical-severity CVE scores 9.9 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.4%, top 67% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
9.9
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 0%CVSS: 9.9Exploit: NoneExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

Wekan is open source kanban built with Meteor. Prior to 9.07, Wekan avatar upload functionality embeds user-supplied filenames into paths later passed to child_process.exec() for MIME-type detection. Because models/avatars.js and models/fileValidation.js used a shell command with the avatar filename, shell metacharacters such as backticks and $() in the filename could execute commands on the server. This issue is fixed in version 9.07.

CVSS v3
9.9
EG Score
9.9(medium)
EG Risk
45(Track)
EG Risk 45/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity99% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS
32.9%
KEV
Not listed

Published

July 15, 2026

Last Modified

July 17, 2026

Advisory Details (3)

Auto-updated Jul 17, 2026
Patch available. Sources: github_release, github, github_commit.
github Patch Available

Wekan: Shell Injection via Avatar Upload · Advisory · wekan/wekan · GitHub

https://github.com/wekan/wekan/security/advisories/GHSA-35j7-h385-2q9g
github_release Patch Available

v9.07

Patch available: wekan/wekan v9.07

https://github.com/wekan/wekan/releases/tag/v9.07
github_commit

commit a4c74a5980e9 (wekan/wekan)

Fix landed in wekan/wekan commit a4c74a5980e9 — awaiting tagged release

https://github.com/wekan/wekan/commit/a4c74a5980e9f778eb444fd346f32aa3d16786a9

Weakness Classification(2)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 10× in last 7d / 13× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-07-24 14:18 UTCEPSS rescore
  2. 2026-07-23 03:19 UTCEG score recompute
  3. 2026-07-22 14:08 UTCEPSS rescore
  4. 2026-07-21 15:25 UTCEPSS rescore
  5. 2026-07-20 17:08 UTCEPSS rescore
  6. 2026-07-19 14:31 UTCEPSS rescore
  7. 2026-07-19 14:31 UTCEPSS rescore
  8. 2026-07-19 02:37 UTCEG score recompute
  9. 2026-07-19 02:29 UTCEPSS rescore
  10. 2026-07-18 10:04 UTCEPSS rescore
  11. 2026-07-16 17:03 UTCEPSS rescore
  12. 2026-07-15 21:24 UTCEG score recompute
  13. 2026-07-15 21:23 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-52891?
CVE-2026-52891 is a critical vulnerability published on July 15, 2026. Wekan is open source kanban built with Meteor. Prior to 9.07, Wekan avatar upload functionality embeds user-supplied filenames into paths later passed to child_process.exec() for MIME-type detection. Because models/avatars.js and models/fileValidation.js used a shell command with the avatar…
When was CVE-2026-52891 disclosed?
CVE-2026-52891 was first published in the National Vulnerability Database on July 15, 2026, with the most recent update on July 17, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-52891 actively exploited?
CVE-2026-52891 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 32.9% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-52891?
CVE-2026-52891 has a CVSS v3 base score of 9.9 (NVD).
How do I remediate CVE-2026-52891?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-52891, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

Explore the affected products and dependency analysis for CVE-2026-52891

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