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CVE-2026-35459 pyload CVE debrief

A critical server-side request forgery (SSRF) vulnerability was found in Pyload-Ng, a free and open-source download manager written in Python. The vulnerability exists in versions 0.5.0b3.dev96 and earlier. An authenticated user with ADD permission can bypass the SSRF fix by submitting a URL that redirects to an internal address. This vulnerability allows attackers to potentially access internal resources, posing a significant risk to affected systems.

Vendor
pyload
Product
Unknown
CVSS
CRITICAL 9.3
CISA KEV
Not listed in stored evidence
Original CVE published
2026-04-06
Original CVE updated
2026-07-24
Advisory published
2026-04-06
Advisory updated
2026-07-24

Who should care

Users of Pyload-Ng, especially those with ADD permissions, should be aware of this vulnerability and take immediate action to update to a patched version. Additionally, security teams and vulnerability management teams should prioritize this vulnerability due to its critical severity and potential impact on internal resources.

Technical summary

The vulnerability is caused by the improper validation of redirect targets in the pycurl configuration. The fix for CVE-2026-33992 added IP validation to BaseDownloader.download(), but it does not account for HTTP redirects. An attacker can exploit this vulnerability by submitting a URL that redirects to an internal address, allowing them to bypass the SSRF filter. This highlights the importance of comprehensive validation for all potential redirect targets.

Defensive priority

High

Recommended defensive actions

  • Update Pyload-Ng to a patched version
  • Restrict ADD permissions to trusted users
  • Monitor for suspicious activity
  • Implement additional security measures to prevent SSRF attacks
  • Review compensating controls for exposed systems while remediation is scheduled and verified
  • Check relevant monitoring, detection, and logs for exposed assets that need extra review
  • Track exceptions, retest remediated assets, and close the item only after evidence is documented

Evidence notes

The vulnerability was reported by an unknown source and is tracked by CVE-2026-35459. The NVD entry is currently Analyzed. Evidence is limited to public sources and may not reflect the full scope or impact of the vulnerability. Defenders should verify affected deployments and review official advisories for specific guidance.

Official resources

AI-assisted PatchSiren debrief based on the supplied source corpus. The CVE record was published on 2026-04-06T20:16:28.220Z and has not been modified since then. The NVD entry is currently Analyzed.