CVE-2026-28681Network attack vector

Account takeover via Host header-poisoned recovery links

Published Mar 6, 2026 · Updated Mar 6, 2026

Host header injection in IRRd 4.4.0 through 4.4.4 and 4.5.0 allows remote attackers to steal account tokens through emailed links. The web UI builds account-creation, password-reset, and mntner-migration email URLs from the request context without constraining the Host header. A recipient must open the poisoned link; the exposed token enables account takeover and RPSL object changes unless two-factor authentication blocks login.

CVSS severity8.1
High
EPSS probability0.43%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Host header injection in IRRd 4.4.0 through 4.4.4 and 4.5.0 allows remote attackers to steal account tokens through emailed links. The web UI builds account-creation, password-reset, and mntner-migration email URLs from the request context without constraining the Host header. A recipient must open the poisoned link; the exposed token enables account takeover and RPSL object changes unless two-factor authentication blocks login.

The record

CVE
CVE-2026-28681
Published
Mar 6, 2026
Updated
Mar 6, 2026
Vendor
IRRd
Product
IRRd
Classifications
CWE-640, CWE-601, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 6, 2026CVE publishedPublication date reported by the CVE source.
  2. Mar 6, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=>= 4.4.0, < 4.4.5
  2. Affected versionversion=>= 4.5.0, < 4.5.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

IRRd · IRRdversion=>= 4.4.0, < 4.4.5; version=>= 4.5.0, < 4.5.1

Published CVSS scores

8.1GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-640Weak Password Recovery Mechanism for Forgotten Password
CWE-601URL Redirection to Untrusted Site ('Open Redirect')
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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