---
title: "CVE-2026-35459: pyLoad: SSRF filter bypass via HTTP redirect in BaseDownloader (Incomplete fix for CVE-2026-33992)"
url: https://erroneo.us/security/cve/CVE-2026-35459/
description: "CVE-2026-35459 (pyload-ng (PyPI)): pyLoad is a free and open-source download manager written in Python. In 0.5.0b3.dev96 and earlier, pyLoad has a…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-04-06
date_modified: 2026-04-07
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-35459"
kev: false
cvss: 9.3
epss: 0.00382
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2026-35459: pyLoad: SSRF filter bypass via HTTP redirect in BaseDownloader (Incomplete fix for CVE-2026-33992)

**Signal:** Critical, preconditions apply. Severe if exploited, but exploitation needs conditions that may not apply to you. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- Not in CISA KEV , but CISA’s SSVC assessment records a public proof-of-concept, so attack code exists.
- EPSS 0.4% , percentile 31: FIRST’s model estimates a 0.4% chance of exploitation activity in the next 30 days, higher than 31% of all scored CVEs (low). EPSS is a probability, not a verdict.
- Needs an account (low (any account)). Exposure depends on who can log in.
- Only applies if your dependency tree includes pyload-ng (PyPI) <= 0.5.0b3.dev96, no fixed version listed . Check your lockfile, including transitive dependencies.

## What it is

pyLoad is a free and open-source download manager written in Python. In 0.5.0b3.dev96 and earlier, pyLoad has a server-side request forgery (SSRF) vulnerability. The fix for CVE-2026-33992 added IP validation to BaseDownloader.download() that checks the hostname of the initial download URL. However, pycurl is configured with FOLLOWLOCATION=1 and MAXREDIRS=10, causing it to automatically follow HTTP redirects. Redirect targets are never validated against the SSRF filter. An authenticated user with ADD permission can bypass the SSRF fix by submitting a URL that redirects to an internal address.

## Affected packages

- PyPI `pyload-ng` <= 0.5.0b3.dev96 → fixed: none listed

## Affected products (CVE record)

- pyload pyload: <= 0.5.0b3.dev96

## Severity

- GitHub_M CVSS 4.0: 9.3 `CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:H/SI:H/SA:N`
- CISA-ADP CVSS 3.1: 9.1 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N`
- GitHub CVSS 4.0: 9.3 `CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:H/SI:H/SA:N`

## Exploitation

- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation poc , automatable yes , technical impact total .
- FIRST EPSS (model of 2026-10-21): 0.38% probability of exploitation activity in the next 30 days; percentile 31.

## Sources

- [GitHub Advisory GHSA-7gvf-3w72-p2pg](https://github.com/advisories/GHSA-7gvf-3w72-p2pg)
- [CVE.org record CVE-2026-35459](https://www.cve.org/CVERecord?id=CVE-2026-35459)
- [NVD entry CVE-2026-35459](https://nvd.nist.gov/vuln/detail/CVE-2026-35459)
- [github.com](https://github.com/pyload/pyload/security/advisories/GHSA-7gvf-3w72-p2pg)
- [github.com](https://github.com/pyload/pyload/commit/33c55da084320430edfd941b60e3da0eb1be9443)
- [nvd.nist.gov](https://nvd.nist.gov/vuln/detail/CVE-2026-33992)

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Source page: https://erroneo.us/security/cve/CVE-2026-35459/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt