High severity · published Feb 3, 2026
CVE-2026-21862
RustFS sourceIp bypass via spoofed X-Forwarded-For/Real-IP headers
7.5
CVSS
0.2%
EPSS
No
On KEV
Description
RustFS is a distributed object storage system built in Rust. Prior to version alpha.78, IP-based access control can be bypassed: get_condition_values trusts client-supplied X-Forwarded-For/X-Real-Ip without verifying a trusted proxy, so any reachable client can spoof aws:SourceIp and satisfy IP-allowlist policies. This issue has been patched in version alpha.78.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 16% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
RU
rustfs · rustfs
< alpha.78 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-21862
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-21862
Vendor Advisory
https://github.com/rustfs/rustfs/security/advisories/GHSA-fc6g-2gcp-2qrq
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