CVE-2026-81836Public exploitNetwork attack vectorHinoki check available

OAuth code disclosure via cleartext callback

Published Aug 27, 2026 · Updated Aug 27, 2026

Cleartext transmission in Roo Code 3.51.0 and 3.51.1 allows remote attackers to read an OAuth authorization code during Claude Code sign-in. The OAuth integration hardcodes http://localhost:54545/callback as the redirect URI, sending the browser's authorization response to an unencrypted HTTP listener. Exploitation requires a Claude Code sign-in and interception of that callback; the reported impact is authorization-code disclosure, not data modification or service interruption.

CVSS severityUnavailable
Unscored
EPSS probability0.19%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Cleartext transmission in Roo Code 3.51.0 and 3.51.1 allows remote attackers to read an OAuth authorization code during Claude Code sign-in. The OAuth integration hardcodes http://localhost:54545/callback as the redirect URI, sending the browser's authorization response to an unencrypted HTTP listener. Exploitation requires a Claude Code sign-in and interception of that callback; the reported impact is authorization-code disclosure, not data modification or service interruption.

The record

CVE
CVE-2026-81836
Published
Aug 27, 2026
Updated
Aug 27, 2026
Vendor
Roo Code, Inc.
Product
Roo Code
Classifications
CWE-310, CWE-319, T1040
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 27, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 27, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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

  1. Affected versionversion=3.51.0
  2. Affected versionversion=3.51.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Roo Code, Inc. · Roo Codeversion=3.51.0; version=3.51.1

Published CVSS scores

6.3VulDB CNACVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:P
3.7VulDB CNACVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N/E:P/RL:X/RC:R
2.6VulDB CNAAV:N/AC:H/Au:N/C:P/I:N/A:N/E:POC/RL:ND/RC:UR
3.7VulDB CNACVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N/E:P/RL:X/RC:R

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 exploitPublished

Weakness, pattern, technique

CWE-310Cryptographic Issues
CWE-319Cleartext Transmission of Sensitive Information
T1040Network Sniffing

Public exploit references

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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