Is CVE-2026-77582 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-77582 being exploited in the wild.

How severe is CVE-2026-77582?

Medium severity, with a CVSS score of 4, published 21 September 2026.

Which products and versions are affected?

github.com/tinyauthapp/tinyauth (Go) < 1.0.1-0.20260714134959-c22925c2fba9, SEMVER:introduced=0,fixed=1.0.1-0.20260714134959-c22925c2fba9.

Is there a fix for CVE-2026-77582?

Yes. github.com/tinyauthapp/tinyauth (Go): upgrade to 1.0.1-0.20260714134959-c22925c2fba9 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-77582 attacked?

It is attacked over the network.

Am I affected by CVE-2026-77582?

Check whether you run github.com/tinyauthapp/tinyauth (Go) or Tinyauth at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-77582: Tinyauth user enumeration via timing oracle

Q: Is there a fix for CVE-2026-77582?

Yes. github.com/tinyauthapp/tinyauth (Go): upgrade to 1.0.1-0.20260714134959-c22925c2fba9 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Q: How is CVE-2026-77582 attacked?

It is attacked over the network.

Q: Am I affected by CVE-2026-77582?

Check whether you run github.com/tinyauthapp/tinyauth (Go) or Tinyauth at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-77582 · Severity: medium · CVSS 4 · Published 2026-09-21

Tinyauth is an authentication server that manages user login attempts. A flaw allows attackers to determine whether a username exists by measuring how long login requests take—existing users have noticeably slower responses (~50ms) than non-existent users (~50µs), revealing valid account names without needing a password.

Technologies: github.com/tinyauthapp/tinyauth (Go), Tinyauth. Vendors: Go.

Quick answers

Is CVE-2026-77582 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-77582 being exploited in the wild.
How severe is CVE-2026-77582?: Medium severity, with a CVSS score of 4, published 21 September 2026.
Which products and versions are affected?: github.com/tinyauthapp/tinyauth (Go) < 1.0.1-0.20260714134959-c22925c2fba9, SEMVER:introduced=0,fixed=1.0.1-0.20260714134959-c22925c2fba9.
Is there a fix for CVE-2026-77582?: Yes. github.com/tinyauthapp/tinyauth (Go): upgrade to 1.0.1-0.20260714134959-c22925c2fba9 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-77582 attacked?: It is attacked over the network.
Am I affected by CVE-2026-77582?: Check whether you run github.com/tinyauthapp/tinyauth (Go) or Tinyauth at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

github.com/tinyauthapp/tinyauth (Go): upgrade to 1.0.1-0.20260714134959-c22925c2fba9 or later
```
go get github.com/tinyauthapp/tinyauth@v1.0.1-0.20260714134959-c22925c2fba9
```

Technical details

The vulnerability is a timing oracle in the user authentication logic. When a login request is processed, the application only performs expensive password-hash verification (bcrypt) for users that exist in the database. For non-existent users, the lookup fails immediately and returns an error without running the hash check, causing a ~1000x timing difference. An attacker can repeatedly attempt login with different usernames and measure response times to enumerate valid accounts. The fix involves performing a dummy bcrypt hash check even when a user is not found, ensuring consistent response times regardless of whether the user exists.

Affected products

Tinyauth

Identifiers

CVE-2026-77582
GHSA-456h-ww26-f758
GO-2026-6555

Timeline

2026-09-22: disclosed
2026-09-22: advisory

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