EUVD-2026-103300Published

Coder before 2.34.2 User Enumeration via Login Placeholder Hash

Collected exploitation and prediction evidence

CISA KEV is observed exploitation evidence. FIRST EPSS is a dated prediction of exploitation in the next 30 days. Missing scores are unknown. This collector requests predictions only for explicit CVE aliases in the public NuGet archive; Microsoft release views retain their existing prediction scope.

No collected risk observation for these identifiers. This does not establish absence of exploitation or a zero probability.

cve-program · CVE-2026-111933

Published

Coder before 2.29.17, 2.30.0 before 2.32.7, 2.33.0 before 2.33.8, and 2.34.0 before 2.34.2 contains a user enumeration vulnerability because userpassword.Compare() substitutes a placeholder hash derived from the string "hunter2" when a stored password hash is empty. Unauthenticated attackers can submit logins with the password "hunter2" and distinguish HTTP 403 from 401 responses to enumerate valid accounts and reveal the authentication provider of SSO-only users.

Source published: 17 Oct 2026 18:46:43 UTC
Source modified: 19 Oct 2026 15:12:57 UTC
Observed here: 23 Oct 2026 15:48:27 UTC
Source terms: CVE Program Terms of Use

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: cve-program · CVE Program Terms of Use. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 4.0 · 6.3 CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N

CVSS 3.1 · 3.7 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N

euvd · EUVD-2026-103300

Published

EUVD source date text has no stated timezone and is retained without inventing a UTC instant. Related bulletin membership is not an alias, common cause or applicability claim. A missing vector with a zero score is treated as unrated. Complete vendor/product and underlying source evidence remains in the original JSON.

Original publisher date fields

datePublished: Oct 17, 2026, 6:46:43 PM

dateUpdated: Oct 19, 2026, 3:12:57 PM

Source published: Oct 17, 2026, 6:46:43 PM (timezone not stated)
Source modified: Oct 19, 2026, 3:12:57 PM (timezone not stated)
Observed here: 7 Nov 2026 04:33:23 UTC
Source terms: ENISA EUVD · source terms and attribution apply

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EUVD CVSS 4.0 · 6.3 CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N

nvd · CVE-2026-111933

Published

NVD analysis and CPE criteria are source context, not proof that a package or your environment is affected. Complete affected data, logical configurations and SSVC are retained in the original JSON.

Source analysis status: Awaiting Analysis

Weakness classifications: CWE-203

Original publisher date fields

published: 2026-10-17T19:16:36.360

lastModified: 2026-10-24T19:10:00.127

Source published: 17 Oct 2026 19:16:36 UTC
Source modified: 24 Oct 2026 19:10:00 UTC
Observed here: 25 Oct 2026 05:17:13 UTC
Source terms: NIST NVD usage terms; underlying source attribution retained

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: nvd · NIST NVD usage terms; underlying source attribution retained. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 4.0 · [email protected] · Secondary · 6.3 CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/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 · [email protected] · Secondary · 3.7 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N

osv · GHSA-8fxq-53rx-ph5f

Published

### Summary `userpassword.Compare()` substituted a placeholder hash derived from the well-known string `"hunter2"` when the stored hash was empty. Submitting `"hunter2"` therefore matched accounts with no password hash (nonexistent users and SSO-only users) and a subsequent login-type check returned an HTTP 403 that disclosed the account's login type, versus 401 for password users. > **Note:** Practical exploitation is limited because the timing side channel is noisy and only reveals whether an account exists. ### Impact An unauthenticated attacker could enumerate valid accounts and their authentication provider by submitting logins with the password `"hunter2"`, distinguishing nonexistent users, SSO users (provider revealed) and password users from the response. This aids credential-stuffing and targeted phishing. No authentication bypass or data access resulted. ### Patches The fix derives the timing-defense placeholder from a secure random value that no supplied password can match. The fix was backported to all supported release lines: | Release line | Patched version | |---|---| | 2.34 | [v2.34.2](https://github.com/coder/coder/releases/tag/v2.34.2) | | 2.33 | [v2.33.8](https://github.com/coder/coder/releases/tag/v2.33.8) | | 2.32 | [v2.32.7](https://github.com/coder/coder/releases/tag/v2.32.7) | | 2.29 (ESR) | [v2.29.17](https://github.com/coder/coder/releases/tag/v2.29.17) | ### Workarounds None. ### References - Fix: #26205 ### Credits We'd like to thank Anthropic's Security Team (ANT-2026-22433) for independently disclosing this issue!

Source published: 20 Aug 2026 18:34:21 UTC
Source modified: 18 Oct 2026 10:55:40 UTC
Observed here: 24 Oct 2026 13:19:41 UTC
Source terms: GitHub Advisory Database · CC-BY-4.0

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS_V3 · CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N

Publisher rating · LOW

osv · GO-2026-6265

Published

Coder: Login endpoint user enumeration via timing-defense placeholder in password comparison in github.com/coder/coder

Source published: 25 Aug 2026 19:43:10 UTC
Source modified: 18 Oct 2026 10:55:40 UTC
Observed here: 24 Oct 2026 13:19:41 UTC
Source terms: OSV · upstream source license applies

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · OSV · upstream source license applies. Source text is retained; field grouping and change labels are provided by ChangeIntel.