Cyber Resilience

CVE-2026-42313

SSRF in Pyload-Ng Project Pyload-Ng ≤ 0.5.0b3.dev100

Published
11 May 2026
Modified
17 June 2026
Patch / advisory
CVSS Score v3.1 8.3
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:L
EPSS Score 0.0040 33th percentile
Risk Priority 61 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2026-42313 is a high-severity Confused Deputy (CWE-441) vulnerability in Pyload-Ng Project Pyload-Ng. Its CVSS base score is 8.3 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 33th 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-16 (Security and Privacy Attributes) and AC-24 (Access Control Decisions) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

pyLoad is a free and open-source download manager written in Python. Prior to 0.5.0b3.dev100, the set_config_value() API method (@permission(Perms.SETTINGS)) in src/pyload/core/api/__init__.py gates security-sensitive options behind a hand-maintained allowlist ADMIN_ONLY_CORE_OPTIONS. The allowlist contains ("proxy", "username") and ("proxy", "password") — which protect…

more

the proxy credentials — but it does not include ("proxy", "enabled"), ("proxy", "host"), ("proxy", "port"), or ("proxy", "type"). Any authenticated user with the non-admin SETTINGS permission can enable proxying and point pyload at any host they control. From that point, every outbound download, captcha fetch, update check, and plugin HTTP call is transparently routed through the attacker. This is a direct continuation of the fix family CVE-2026-33509 / CVE-2026-35463 / CVE-2026-35464 / CVE-2026-35586, each of which patched a different missed option in the same allowlist. This vulnerability is fixed in 0.5.0b3.dev100.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
T1090 Proxy Command And Control
Adversaries may use a connection proxy to direct network traffic between systems or act as an intermediary for network communications to a command and control server to avoid direct connections to their infrastructure.
T1090.001 Internal Proxy Command And Control
Adversaries may use an internal proxy to direct command and control traffic between two or more systems in a compromised environment.
T1090.002 External Proxy Command And Control
Adversaries may use an external proxy to act as an intermediary for network communications to a command and control server to avoid direct connections to their infrastructure.
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.
T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-35187Same product: Pyload-Ng Project Pyload-Ng
CVE-2026-35459Same product: Pyload-Ng Project Pyload-Ng
CVE-2026-46717Shared CWE-863, CWE-918
CVE-2026-63443Shared CWE-863, CWE-918
CVE-2026-41689Shared CWE-863, CWE-918
CVE-2023-32683Shared CWE-863, CWE-918
CVE-2023-25923Shared CWE-863
CVE-2024-40771Shared CWE-863
CVE-2023-34197Shared CWE-863
CVE-2024-56348Shared CWE-863

Affected Assets

pyload-ng project
pyload-ng
≤ 0.5.0b3.dev100

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)
  • 5 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V3.2.1
  • V3.5.1
  • V3.5.3
  • V3.5.8

Mitigating Controls (NIST 800-53 r5) AI

AC-3 directly requires correct enforcement of authorization decisions on every access request, structurally preventing incorrect checks.

Associating and preserving security attributes such as original source identity prevents the loss of provenance that creates the confused deputy.

AC-24 ensures access-control decisions are made and applied consistently, reducing the chance of an incorrect authorization result.

A reference monitor that is always invoked and tamper-proof forces every authorization decision through a verified, correct path.

Information flow enforcement requires preserving and checking source attributes before forwarding requests outside the trust boundary.

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

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.

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.AA-04 partial match
prevents

Proper conveyance and verification of original identity assertions directly prevents loss of request source when forwarding.

PR.AA-05 partial match
prevents

Enforcing least-privilege authorizations on forwarded requests reduces confused-deputy abuse even if source identity is lost.

PR.IR-01 partial match
prevents

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

PR.PS-06 partial match
prevents

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

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

Access-control rules can limit which upstream identities may cause the product to act on their behalf, reducing confused-deputy risk.

prevents

Proper identity management ensures the original requester identity is preserved and validated before the product forwards requests.

degrades

Explicit access-rights assignment can restrict the product’s ability to act as an unintended proxy for external actors.

prevents

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

degrades

Privileged-access controls limit the rights the product may exercise on behalf of upstream callers, mitigating confused-deputy abuse.

degrades

Network-security controls can enforce source validation and prevent the product from blindly proxying traffic to external actors.

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` (higher-evidence rows only; rows rated `none` are excluded).

Oracle Linux 8 (2 rules)
  • V-248581 OL 8 must require users to provide a password for privilege escalation. prevents CWE-863
  • V-252656 The OL 8 operating system must not be configured to bypass password requirements for privilege escalation. prevents CWE-863
RHEL 7 (1 rule)
  • V-204430 The Red Hat Enterprise Linux operating system must be configured so that users must re-authenticate for privilege escalation. prevents CWE-863
RHEL 8 (1 rule)
  • V-251712 The RHEL 8 operating system must not be configured to bypass password requirements for privilege escalation. prevents CWE-863

References