medium CVSS 6.8 EPSS 0.17%

CVE-2026-42312·Python vulnerability

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 option ("general", "ssl_verify") is not on that allowlist. Any authenticated user with the non-admin SETTINGS permission can set general.ssl_verify = off, and every subsequent outbound pycurl request is made with SSL_VERIFYPEER=0 and SSL_VERIFYHOST=0 — TLS peer and hostname verification are fully disabled. An on-path attacker can then present forged certificates for any hostname pyload fetches. 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.

Severity
medium
Software
Python
Fixed in
0.5.0b3.dev100
Published

How likely is exploitation

FIRST's Exploit Prediction Scoring System puts the probability of this CVE being exploited in the next 30 days at 0.17% — higher than 7% of all published CVEs. EPSS is an independent forecast of exploitation, not a severity rating: it says nothing about how much damage a successful attack does, which is what a CVSS score measures.

Affected versions

Until: 0.5.0b3.dev100

Fixed in: 0.5.0b3.dev100

How to fix this CVE

Update pyLoad to version 0.5.0b3.dev100 or later to prevent authenticated users from disabling SSL/TLS verification. This vulnerability allows non-admin users with SETTINGS permissions to disable certificate validation, creating an attack surface for man-in-the-path interception. Apply the patch immediately if pyLoad is deployed in your environment.

sudo dnf update python3-pyload || pip install --upgrade pyload>=0.5.0b3.dev100

Defensia detects this vulnerability

How to check if you are affected

  1. Check the installed pyLoad version: pip show pyload | grep Version
  2. List all users with SETTINGS permission in pyLoad config and audit recent permission grants: grep -r 'Perms.SETTINGS' ~/.config/pyload/ 2>/dev/null || cat /etc/pyload/config.cfg | grep -i permission
  3. Search pyLoad logs for set_config_value calls targeting 'ssl_verify': grep -i 'set_config_value.*ssl_verify' /var/log/pyload/*.log /home/*/.pyload/logs/*.log 2>/dev/null
  4. Verify the ssl_verify setting is not disabled: grep -r 'ssl_verify.*off\|ssl_verify.*false\|ssl_verify.*0' ~/.config/pyload/ /etc/pyload/ 2>/dev/null

FAQ

What is CVE-2026-42312?

CVE-2026-42312 is a configuration bypass vulnerability in pyLoad that allows authenticated non-admin users to disable SSL/TLS peer and hostname verification by modifying the 'general.ssl_verify' setting, enabling man-in-the-path attackers to intercept encrypted connections with forged certificates.

Is CVE-2026-42312 being actively exploited?

No, this vulnerability is not listed on the CISA Known Exploited Vulnerabilities (KEV) catalog and no public exploits are currently available, but it should still be patched promptly due to its ease of exploitation by internal threat actors.

What versions of pyLoad are affected by CVE-2026-42312?

All versions of pyLoad prior to 0.5.0b3.dev100 are affected. The vulnerability is rooted in incomplete allowlist maintenance for security-sensitive configuration options.

How do I check if my server is vulnerable to CVE-2026-42312?

Run 'pip show pyload | grep Version' and verify the version number is 0.5.0b3.dev100 or later. Also check pyLoad's configuration files for 'ssl_verify = off' or similar disabled settings.

Does Defensia detect CVE-2026-42312?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If pyLoad is installed on a monitored server, CVE-2026-42312 will appear in your dashboard with remediation steps.

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References

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