CVE-2026-48737

MEDIUMPre-NVD 4.94.9—
EchelonGraph scoreMEDIUM confidence

Score 4.9 from GitHub Security Advisory published 2026-07-09. a secondary CVSS source baseline 4.9; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 3 sources updated this weekElevated
4.9EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 4.9Exploit: Elevated riskExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

pyLoad is a free and open-source download manager written in Python. Prior to 0.5.0b3.dev101, is_global_address in src/pyload/core/utils/web/check.py relies on Python's global-address classification without examining IPv4 destinations embedded in 6to4 or NAT64 IPv6 addresses. A low-privileged user can submit an IPv6 literal through parse_urls to the pre-resolution is_global_host guard. Because host_to_ip is pinned to AF_INET, that guard does not evaluate a hostname's AAAA result. Separately, curl resolves hostnames before the pycurl PREREQFUNC in src/pyload/core/network/http/http_request.py applies the same vulnerable is_global_address check to the actual connection address, so a transition-form AAAA result can be permitted even when it terminates at an embedded loopback, private, CGNAT, or link-local IPv4 address. Exploitation requires the pyLoad host to route the applicable transition mechanism, including 6to4 on affected Python 3.9 through 3.11 deployments or NAT64 on a network with a NAT64 gateway. Successful exploitation can enable internal-network reconnaissance, timing-based confirmation, limited service disruption, or cloud metadata disclosure where the wrapped address is routable. This issue is fixed in version 0.5.0b3.dev101.

CVSS v3
4.9
EG Score
4.9(medium)
EG Risk
38(Track)
EG Risk 38/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity49% × 45%
Exploitation40% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
8%
KEV
Not listed

Published

July 9, 2026

Last Modified

September 16, 2026

Advisory Details (2)

Auto-updated Sep 15, 2026
🔬 Proof of concept available. Patch available. Sources: github, github_commit.
github_commit

commit ba7491046b2d (pyload/pyload)

Fix landed in pyload/pyload commit ba7491046b2d — awaiting tagged release

https://github.com/pyload/pyload/commit/ba7491046b2d430732be490913e4cbf1f1e899c2
github Patch Available🟡 PoC Available

SSRF guard bypass via IPv6 6to4/NAT64 transition wrappers of internal IPs · Advisory · pyload/pyload · GitHub

https://github.com/pyload/pyload/security/advisories/GHSA-m5x5-28jr-gpjj

Vendor Advisories for CVE-2026-48737(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Patch Availability(1)

Vendor / EcosystemFixed in / PatchReleasedSource
pippyload-ng—ghsa

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(1 across 1 ecosystem)
PyPI(1)
PackageVulnerable rangeFixed inDependents
pyload-ng0.5.0a5.dev528 ... 0.5.0b3.dev99 (105 versions)——

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 14× in last 7d / 24× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-09-18 19:28 UTCEPSS rescore
  2. 2026-09-18 05:37 UTCEG score recompute
  3. 2026-09-18 05:37 UTCGHSA enrichment
  4. 2026-09-16 17:53 UTCEG score recompute
  5. 2026-09-16 17:53 UTCGHSA enrichment
  6. 2026-09-16 17:11 UTCEG score recompute
  7. 2026-09-16 17:11 UTCGHSA enrichment
  8. 2026-09-16 14:08 UTCEPSS rescore
  9. 2026-09-16 13:47 UTCGHSA enrichment
  10. 2026-09-15 15:35 UTCEG score recompute
  11. 2026-09-15 15:35 UTCGHSA enrichment
  12. 2026-09-15 14:43 UTCGHSA enrichment
  13. 2026-09-14 08:55 UTCGHSA enrichment
  14. 2026-09-13 08:20 UTCGHSA enrichment
  15. 2026-09-12 03:25 UTCGHSA enrichment
  16. 2026-09-05 22:36 UTCGHSA enrichment
  17. 2026-08-30 06:56 UTCGHSA enrichment
  18. 2026-08-27 21:46 UTCGHSA enrichment
  19. 2026-08-26 08:19 UTCGHSA enrichment
  20. 2026-08-25 07:31 UTCGHSA enrichment
  21. 2026-08-24 06:55 UTCGHSA enrichment
  22. 2026-08-23 06:19 UTCGHSA enrichment
  23. 2026-08-22 05:43 UTCGHSA enrichment
  24. 2026-08-21 05:07 UTCGHSA enrichment
  25. 2026-08-20 04:31 UTCGHSA enrichment
Show 37 more
  1. 2026-08-19 03:54 UTCGHSA enrichment
  2. 2026-08-18 02:55 UTCGHSA enrichment
  3. 2026-08-17 01:22 UTCGHSA enrichment
  4. 2026-08-16 00:46 UTCGHSA enrichment
  5. 2026-08-15 00:10 UTCGHSA enrichment
  6. 2026-08-13 23:35 UTCGHSA enrichment
  7. 2026-08-12 22:59 UTCGHSA enrichment
  8. 2026-08-11 22:24 UTCGHSA enrichment
  9. 2026-08-10 21:48 UTCGHSA enrichment
  10. 2026-08-09 21:12 UTCGHSA enrichment
  11. 2026-08-08 20:37 UTCEG score recompute
  12. 2026-08-08 20:37 UTCGHSA enrichment
  13. 2026-08-07 20:01 UTCGHSA enrichment
  14. 2026-08-06 19:25 UTCGHSA enrichment
  15. 2026-08-05 18:49 UTCGHSA enrichment
  16. 2026-08-04 18:14 UTCGHSA enrichment
  17. 2026-08-03 17:29 UTCGHSA enrichment
  18. 2026-08-02 16:53 UTCGHSA enrichment
  19. 2026-08-01 16:17 UTCGHSA enrichment
  20. 2026-07-31 15:41 UTCGHSA enrichment
  21. 2026-07-30 15:04 UTCEG score recompute
  22. 2026-07-30 15:04 UTCGHSA enrichment
  23. 2026-07-29 14:21 UTCGHSA enrichment
  24. 2026-07-28 13:42 UTCGHSA enrichment
  25. 2026-07-27 13:04 UTCGHSA enrichment
  26. 2026-07-26 12:20 UTCEG score recompute
  27. 2026-07-26 12:20 UTCGHSA enrichment
  28. 2026-07-23 03:18 UTCEG score recompute
  29. 2026-07-16 18:04 UTCGHSA enrichment
  30. 2026-07-15 17:28 UTCGHSA enrichment
  31. 2026-07-14 16:48 UTCGHSA enrichment
  32. 2026-07-13 16:12 UTCGHSA enrichment
  33. 2026-07-12 15:35 UTCGHSA enrichment
  34. 2026-07-11 14:59 UTCGHSA enrichment
  35. 2026-07-10 14:23 UTCGHSA enrichment
  36. 2026-07-09 13:45 UTCEG score recompute
  37. 2026-07-09 13:45 UTCGHSA enrichment

Frequently asked(5)

What is CVE-2026-48737?
CVE-2026-48737 is a medium vulnerability published on July 9, 2026. pyLoad is a free and open-source download manager written in Python. Prior to 0.5.0b3.dev101, isglobaladdress in src/pyload/core/utils/web/check.py relies on Python's global-address classification without examining IPv4 destinations embedded in 6to4 or NAT64 IPv6 addresses. A low-privileged user…
When was CVE-2026-48737 disclosed?
CVE-2026-48737 was first published in the National Vulnerability Database on July 9, 2026, with the most recent update on September 16, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-48737 actively exploited?
CVE-2026-48737 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 92.0% of all scored CVEs.
What is the CVSS score of CVE-2026-48737?
CVE-2026-48737 has a CVSS v3 base score of 4.9 (NVD).
How do I remediate CVE-2026-48737?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-48737, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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