CVE-2026-48858: ftp client PASV response IP not validated against control peer, enabling SSRF and FTP bounce attacks
CSIRTS triage
- What
- The PASV response IP is not validated against the control peer, allowing SSRF and FTP bounce attacks.
- Who is affected
- Users of the affected FTP client.
- Urgency
- Remediation is important due to the medium severity rating and potential for exploitation.
- Action
- Implement validation checks or update the FTP client.
AI-assisted analysis generated from the source advisory — verify against the original.
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Details
Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-48858
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Low exploitation riskCVE-2026-488580.23% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 14% of all scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2026-48858 | coverage & exploitation status | NVD · CVE.org |
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