CVE-2026-21862 | RustFS sourceIp bypass via spoofed X-Forwarded-For/Real-IP headers

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.

Published: 2026-02-03 Last update: 2026-02-23 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-21862 is rated Low Risk (34.8/100): CVSS High severity, with low exploitation likelihood (EPSS 0.04%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-21862

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-02-24 0.05% 0.04% -0.02%
2 2026-02-09 0.04% 0.05% +0.01%
3 2026-02-04 — 0.04% —

Full EPSS history (3 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-21862

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.7 4.0 HIGH
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network.
Attack complexity (AC:L)
Exploitation conditions are straightforward and stable.
Attack requirements (AT:N)
No additional preconditions are required beyond normal reachability.
Privileges required (PR:N)
No privileges are required.
User interaction (UI:N)
No user interaction is required.
Vulnerable system confidentiality impact (VC:N)
No confidentiality impact on the vulnerable system.
Vulnerable system integrity impact (VI:H)
High integrity impact on the vulnerable system.
Vulnerable system availability impact (VA:N)
No availability impact on the vulnerable system.
Subsequent system confidentiality impact (SC:N)
No confidentiality impact on subsequent systems.
Subsequent system integrity impact (SI:N)
No integrity impact on subsequent systems.
Subsequent system availability impact (SA:N)
No availability impact on subsequent systems.
Exploit maturity (threat) (E:P)
Proof-of-concept: public PoC exists; no reported exploitation and no known simplification tools.
Confidentiality requirement (CR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Integrity requirement (IR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Availability requirement (AR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Modified attack vector (MAV:X)
Not defined: scoring uses the Base Attack Vector (AV).
Modified attack complexity (MAC:X)
Not defined: scoring uses the Base Attack Complexity (AC).
Modified attack requirements (MAT:X)
Not defined: scoring uses the Base Attack Requirements (AT).
Modified privileges required (MPR:X)
Not defined: scoring uses the Base Privileges Required (PR).
Modified user interaction (MUI:X)
Not defined: scoring uses the Base User Interaction (UI).
Modified vulnerable system confidentiality impact (MVC:X)
Not defined: scoring uses the Base VC metric.
Modified vulnerable system integrity impact (MVI:X)
Not defined: scoring uses the Base VI metric.
Modified vulnerable system availability impact (MVA:X)
Not defined: scoring uses the Base VA metric.
Modified subsequent system confidentiality impact (MSC:X)
Not defined: scoring uses the Base SC metric.
Modified subsequent system integrity impact (MSI:X)
Not defined: scoring uses the Base SI metric.
Modified subsequent system availability impact (MSA:X)
Not defined: scoring uses the Base SA metric.
Safety (supplemental) (S:X)
Not evaluated.
Automatable (supplemental) (AU:X)
Not evaluated.
Recovery (supplemental) (R:X)
Not evaluated.
Value density (supplemental) (V:X)
Not evaluated.
Vulnerability response effort (supplemental) (RE:X)
Not evaluated.
Provider urgency (supplemental) (U:X)
Not evaluated.
 — — [email protected]
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 3.6 [email protected]

Weakness enumeration for CVE-2026-21862

GitHub Security Advisory for CVE-2026-21862

GHSA-fc6g-2gcp-2qrq · Severity: high · Ecosystem: rust — RustFS has SourceIp bypass via spoofed X-Forwarded-For/Real-IP headers

Affected software / configurations for CVE-2026-21862

Vendor Product Version Raw CPE
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha1:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha10:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha11:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha12:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha13:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha14:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha15:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha16:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha17:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha18:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha19:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha2:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha20:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha21:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha22:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha23:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha24:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha25:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha26:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha27:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha28:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha29:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha3:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha30:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha31:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha32:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha33:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha34:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha35:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha36:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha37:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha38:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha39:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha4:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha40:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha41:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha42:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha43:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha44:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha45:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha46:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha47:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha48:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha49:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha5:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha50:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha51:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha52:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha53:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha54:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha55:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha56:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha57:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha58:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha59:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha6:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha60:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha61:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha62:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha63:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha64:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha65:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha66:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha67:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha68:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha69:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha7:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha70:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha71:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha72:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha73:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha74:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha75:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha76:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha77:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha8:*:*:*:rust:*:*
rustfs rustfs 1.0.0 cpe:2.3:a:rustfs:rustfs:1.0.0:alpha9:*:*:*:rust:*:*

References for CVE-2026-21862

cvelogic Threat Intelligence