CVE-2026-86257Public exploitNetwork attack vector

Admin data exfiltration via unsanitized member export

Published Sep 6, 2026 · Updated Sep 8, 2026

CSV formula injection in wger 2.5.0 and earlier allows remote authenticated users to execute formulas through gym member exports. The gym export view passes stored first_name and last_name values directly to csv.writer, which leaves formula-leading characters unneutralized. A gym administrator must export and open the TSV in a formula-evaluating spreadsheet, enabling data exfiltration or legacy Excel DDE code execution.

CVSS severity7.4
High
EPSS probability0.17%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

CSV formula injection in wger 2.5.0 and earlier allows remote authenticated users to execute formulas through gym member exports. The gym export view passes stored first_name and last_name values directly to csv.writer, which leaves formula-leading characters unneutralized. A gym administrator must export and open the TSV in a formula-evaluating spreadsheet, enabling data exfiltration or legacy Excel DDE code execution.

The record

CVE
CVE-2026-86257
Published
Sep 6, 2026
Updated
Sep 8, 2026
Vendor
wger Project
Product
wger
Classifications
CWE-1236, T1204.002
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 6, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 8, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <2.6

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

wger Project · wgerversion=0 <2.6

Published CVSS scores

7.4wger ProjectCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-1236Improper Neutralization of Formula Elements in a CSV File
T1204.002Malicious File

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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