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TI-2026-36957 Aliases CVE-2026-50198

Wallos: Cross-user subscription cost inference via replacement_subscription_id

Priority MEDIUM 53CWE-639Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
Low · None · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-639.

Summary

Wallos is an open-source, self-hostable personal subscription tracker. Prior to version 4.9.1, an authenticated user can edit their own inactive subscription and set replacement_subscription_id to a subscription ID belonging to another user. The write is accepted, and later the stats logic dereferences that foreign subscription ID without user_id scoping. This lets the attacker infer the victim subscription's monthly-normalized cost by observing changes in their own stats output. This does not expose the full victim subscription object, but it does expose derived financial metadata. This issue has been patched in version 4.9.1.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00294 22nd percentileScored 2026-11-07
Fix Fixed Wallos (ellite): 4.9.1

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
elliteWallosbefore 4.9.14.9.1Patch availableCNA
  • Wallos Vendorellite Affected before 4.9.1 Fixed in 4.9.1 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:wallosapp:wallos:*:*:*:*:*:*:*:*——ellite
  • cpe:2.3:a:wallosapp:wallos:*:*:*:*:*:*:*:* Versions — — ·ellite

Remediation

  • Fix · CNA Wallos (ellite) Fixed in 4.9.1

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-50198

References

Other 2

  • TI-2026-53972 Server-side request forgery in ellite Wallos CVSS 3.1HIGH 8.2
  • TI-2026-39433 Wallos: Unauthenticated database replacement via import endpoint on fresh install CVSS 4.0HIGH 8.2
  • TI-2026-25804 Wallos: SSRF via HTTP Proxy Environment Variable CVSS 4.0HIGH 8.3
  • TI-2026-23669 Wallos: Server-Side Request Forgery (SSRF) in Notification Testers CVSS 3.0HIGH 8.8
  • TI-2026-39431 Missing Authentication for Critical Function in wallos CVSS 3.1HIGH 7.5
  • TI-2026-39432 Wallos: OIDC state parameter never validated — login CSRF / account takeover CVSS 4.0HIGH 7.5
See all 31 →

Sources

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