CVE-2026-45773
Turborepo: Login callback CSRF/session fixation
Turborepo is a high-performance build system for JavaScript and TypeScript codebases. Prior to 2.9.14, Turborepo's self-hosted login and SSO browser flows did not validate a CSRF state value on the localhost callback. While the CLI was waiting for authentication, a malicious web page could send a request to the local callback server with an attacker-controlled token. If accepted before the legitimate callback, the CLI could complete login with the wrong credentials. This affects users authenticating the turbo CLI against self-hosted remote cache/auth endpoints. Vercel-hosted login flows using device authorization are not affected. This vulnerability is fixed in 2.9.14.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Passive
What an attacker can affect
- Confidentiality
- None
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
5.1
Turborepo: Login callback CSRF/session fixation
Turborepo is a high-performance build system for JavaScript and TypeScript codebases. Prior to 2.9.14, Turborepo's self-hosted login and SSO browser flows did not validate a CSRF state value on the localhost callback. While the CLI was waiting for authentication, a malicious web page could send a request to the local callback server with an attacker-controlled token. If accepted before the legitimate callback, the CLI could complete login with the wrong credentials. This affects users authenticating the turbo CLI against self-hosted remote cache/auth endpoints. Vercel-hosted login flows using device authorization are not affected. This vulnerability is fixed in 2.9.14.
- Record
CVE-2026-45773- CVSS 4.0
- 5.1 Medium
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:L/VA:N/SC:L/SI:H/SA:N - Weakness
- CWE-352, CWE-384
- Updated
- 2026-11-02
EUVDEUVD-2026-30553
5.1
Turborepo is a high-performance build system for JavaScript and TypeScript codebases. Prior to 2.9.14, Turborepo's self-hosted login and SSO browser flows did not validate a CSRF state value on the localhost callback. While the CLI was waiting for authentication, a malicious web page could send a request to the local callback server with an attacker-controlled token. If accepted before the legitimate callback, the CLI could complete login with the wrong credentials. This affects users authenticating the turbo CLI against self-hosted remote cache/auth endpoints. Vercel-hosted login flows using device authorization are not affected. This vulnerability is fixed in 2.9.14.
- Record
EUVD-2026-30553- CVSS 4.0
- 5.1 Medium
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:L/VA:N/SC:L/SI:H/SA:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-hcf7-66rw-9f5r
5.1
Turbo: Login callback CSRF/session fixation
Impact
Turborepo's self-hosted login and SSO browser flows did not validate a CSRF state value on the localhost callback. While the CLI was waiting for authentication, a malicious web page could send a request to the local callback server with an attacker-controlled token. If accepted before the legitimate callback, the CLI could complete login with the wrong credentials.
This affects users authenticating the turbo CLI against self-hosted remote cache/auth endpoints. Vercel-hosted login flows using device authorization are not affected.
Fix
The login and SSO redirect flows now generate a random state value, include it in the browser authentication URL, and require the same value on the localhost callback before accepting a token. Callbacks with a missing or mismatched state are rejected.
Workarounds
If you cannot upgrade immediately, avoid browser-based self-hosted turbo login or SSO flows on machines that may load untrusted web content during authentication. Use a pre-provisioned token or environment-based authentication instead.
- Record
GHSA-hcf7-66rw-9f5r- CVSS 4.0
- 5.1 Medium
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:L/VA:N/SC:L/SI:H/SA:N - Weakness
- CWE-352
- Updated
- 2026-11-02
NVD
5.1
Turborepo is a high-performance build system for JavaScript and TypeScript codebases. Prior to 2.9.14, Turborepo's self-hosted login and SSO browser flows did not validate a CSRF state value on the localhost callback. While the CLI was waiting for authentication, a malicious web page could send a request to the local callback server with an attacker-controlled token. If accepted before the legitimate callback, the CLI could complete login with the wrong credentials. This affects users authenticating the turbo CLI against self-hosted remote cache/auth endpoints. Vercel-hosted login flows using device authorization are not affected. This vulnerability is fixed in 2.9.14.
- Record
CVE-2026-45773- CVSS 4.0
- 5.1 Medium
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:L/VA:N/SC:L/SI:H/SA:N/E:X/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 - CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N - Weakness
- CWE-352, CWE-384
- Updated
- 2026-11-02
OSV
5.1
Turborepo: Login callback CSRF/session fixation
Turborepo is a high-performance build system for JavaScript and TypeScript codebases. Prior to 2.9.14, Turborepo's self-hosted login and SSO browser flows did not validate a CSRF state value on the localhost callback. While the CLI was waiting for authentication, a malicious web page could send a request to the local callback server with an attacker-controlled token. If accepted before the legitimate callback, the CLI could complete login with the wrong credentials. This affects users authenticating the turbo CLI against self-hosted remote cache/auth endpoints. Vercel-hosted login flows using device authorization are not affected. This vulnerability is fixed in 2.9.14.
- Record
CVE-2026-45773- CVSS 4.0
- 5.1 Medium
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:L/VA:N/SC:L/SI:H/SA:N - Weakness
- CWE-352, CWE-384
- Updated
- 2026-11-02
OSVGHSA-hcf7-66rw-9f5r
5.1
Turbo: Login callback CSRF/session fixation
Impact
Turborepo's self-hosted login and SSO browser flows did not validate a CSRF state value on the localhost callback. While the CLI was waiting for authentication, a malicious web page could send a request to the local callback server with an attacker-controlled token. If accepted before the legitimate callback, the CLI could complete login with the wrong credentials.
This affects users authenticating the turbo CLI against self-hosted remote cache/auth endpoints. Vercel-hosted login flows using device authorization are not affected.
Fix
The login and SSO redirect flows now generate a random state value, include it in the browser authentication URL, and require the same value on the localhost callback before accepting a token. Callbacks with a missing or mismatched state are rejected.
Workarounds
If you cannot upgrade immediately, avoid browser-based self-hosted turbo login or SSO flows on machines that may load untrusted web content during authentication. Use a pre-provisioned token or environment-based authentication instead.
- Record
GHSA-hcf7-66rw-9f5r- CVSS 4.0
- 5.1 Medium
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:L/VA:N/SC:L/SI:H/SA:N - Weakness
- CWE-352
- Updated
- 2026-11-02
Affected products
Affected packages
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-45773 is a medium vulnerability (CVSS 5.1) in Vercel Turborepo, published May 15, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.12%, the 2nd percentile. Fixed in turbo 2.9.14.