Cyber Resilience

CVE-2026-33407

SSRF in Wallosapp Wallos ≤ 4.7.0

Public PoCSSRF
Published
24 March 2026
Modified
26 March 2026
Patch / advisory
CVSS Score v4 8.3
Click a component to see what it means
Raw vectorCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS Score 0.0037 30th percentile
Risk Priority 43 floored blend · peak EPSS

Summary

CVE-2026-33407 is a high-severity SSRF (CWE-918) vulnerability in Wallosapp Wallos. Its CVSS base score is 8.3 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Unsecured Credentials (T1552); ranked at the 30th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to AC-3 (Access Enforcement) and AC-4 (Information Flow Enforcement) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2026-33407 is a server-side request forgery (SSRF) vulnerability, associated with CWE-918 and CWE-922, affecting Wallos, an open-source, self-hostable personal subscription tracker, in versions prior to 4.7.0. The issue stems from the endpoints/logos/search.php component, which accepts HTTP_PROXY and HTTPS_PROXY environment variables without validation, enabling SSRF via proxy hijacking. Additionally, the server performs DNS resolution on user-supplied search terms in this endpoint, allowing outbound requests to arbitrary domains.

Attackers can exploit this vulnerability remotely over the network (AV:N) with low attack complexity (AC:L), requiring no privileges (PR:N) or user interaction (UI:N), and without changing the scope (S:U). Exploitation yields high impacts on confidentiality (C:H) and availability (A:H), with no integrity impact (I:N), as rated by its CVSS v3.1 score of 9.1. Remote unauthenticated attackers can control search terms or proxy settings to force the server to resolve and connect to arbitrary domains, potentially enabling internal network scanning, data exfiltration, or denial-of-service conditions.

The vulnerability has been patched in Wallos version 4.7.0. Mitigation involves upgrading to this version or later. Further details on the fix are provided in the GitHub security advisory at GHSA-hhjq-82f8-m6rc and the patching commit at e87387f0ebb540cd33e6dfda7181db9db650ecef.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Wallos is an open-source, self-hostable personal subscription tracker. Prior to version 4.7.0, Wallos endpoints/logos/search.php accepts HTTP_PROXY and HTTPS_PROXY environment variables without validation, enabling SSRF via proxy hijacking. The server performs DNS resolution on user-supplied search terms, which can be controlled…

more

by attackers to trigger outbound requests to arbitrary domains. This issue has been patched in version 4.7.0.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1552 Unsecured Credentials Credential Access
Adversaries may search compromised systems to find and obtain insecurely stored credentials.
T1552.001 Credentials In Files Credential Access
Adversaries may search local file systems and remote file shares for files containing insecurely stored credentials.
T1552.004 Private Keys Credential Access
Adversaries may search for private key certificate files on compromised systems for insecurely stored credentials.
T1552.006 Group Policy Preferences Credential Access
Adversaries may attempt to find unsecured credentials in Group Policy Preferences (GPP).
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1552.002 Credentials in Registry Credential Access
Adversaries may search the Registry on compromised systems for insecurely stored credentials.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-30839Same product: Wallosapp Wallos
CVE-2026-33399Same product: Wallosapp Wallos
CVE-2026-27479Same product: Wallosapp Wallos
CVE-2026-30828Same product: Wallosapp Wallos
CVE-2026-30840Same product: Wallosapp Wallos
CVE-2026-33401Same product: Wallosapp Wallos
CVE-2024-29320Same product: Wallosapp Wallos
CVE-2024-55371Same product: Wallosapp Wallos
CVE-2024-55372Same product: Wallosapp Wallos
CVE-2024-57386Same product: Wallosapp Wallos

Affected Assets

wallosapp
wallos
≤ 4.7.0

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 3 hardening rules · 2 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V1.3.6
  • V1.5.3
  • V5.3.2
  • V10.4.7

Mitigating Controls (NIST 800-53 r5) AI

Enforces approved authorizations for logical access to stored information, directly stopping unauthorized read/write.

Requires protection of confidentiality/integrity for information at rest, directly addressing insecure storage.

Information flow enforcement can restrict which destinations the server is allowed to contact on behalf of users.

Limits privileges so only authorized accesses to sensitive stored data are permitted.

Input validation directly stops untrusted URLs from being accepted and fetched without destination checks.

Associates security attributes with information to support proper access decisions on storage.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.AA-05 mostly match
prevents

Enforces least-privilege permissions and authorization reviews that limit read/write access to stored sensitive data.

PR.DS-01 mostly match
prevents

Directly protects data-at-rest confidentiality via encryption or access controls that prevent unauthorized reads.

PR.PS-06 mostly match
prevents

Secure development practices directly include input validation and destination allow-listing that prevent SSRF.

DE.CM-09 partial match
prevents

Runtime monitoring of web applications and services can detect anomalous outbound requests indicative of SSRF.

ID.RA-01 partial match
prevents

Vulnerability identification processes can discover and record SSRF flaws in web applications.

PR.IR-01 partial match
prevents

Network segmentation and egress controls can limit the damage from successful SSRF requests.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

prevents

Operational threat data describing SSRF campaigns can be used to tighten outbound-request allow-lists and detection rules before attackers exploit them.

mitigates

Secure reuse and disposal procedures, including cryptographic wiping and physical destruction, stop the insecure storage of sensitive data on media that may later be accessed by unauthorized actors.

prevents

Mandating secure disposal techniques stops the insecure retention of sensitive information on storage media that leaves organizational control.

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).

Windows Server 2016 (2 rules)
  • V-224973 The Active Directory Domain Controllers Organizational Unit (OU) object must have the proper access control permissions. prevents CWE-922
  • V-224974 Domain-created Active Directory Organizational Unit (OU) objects must have proper access control permissions. prevents CWE-922
Windows Server 2019 (1 rule)
  • V-205743 Windows Server 2019 organization created Active Directory Organizational Unit (OU) objects must have proper access control permissions. prevents CWE-922

References