GHSA-gxhx-2686-5h9g
slack-go `SecretsVerifier` accepts empty signing secret without precondition
GHSA-gxhx-2686-5h9g is a medium vulnerability (CVSS 4.8) in github.com/slack-go/slack, published May 14, 2026. No source lists public exploit code. Fixed in github.com/slack-go/slack 0.23.1.
- Severity
- 4.8 MediumCVSS 4.0, GitHub Advisories
- Exploit chance
- UnscoredNo EPSS score yet
- Exploitation
- None knownNot on CISA’s or ENISA’s lists
- Fixed in
0.23.1github.com/slack-go/slack
Description
SecretsVerifier in slack-go/slack before v0.23.1 accepts an empty signing secret without error. If an application is misconfigured (e.g., an unset or empty SLACK_SIGNING_SECRET), NewSecretsVerifier builds an HMAC-SHA256 keyed with an empty string, allowing an unauthenticated attacker to forge a valid X-Slack-Signature and bypass Slack request authentication. Fixed in v0.23.1, which rejects empty secrets with ErrInvalidConfiguration. This is patched in version 0.23.1.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- Low
- Integrity
- High
- Availability
- None
Affected packages
| Package | Affected | Fixed |
|---|---|---|
github.com/slack-go/slackGo | before 0.23.1 | 0.23.1 |
What each source reports
GitHub Advisories Score used
slack-go `SecretsVerifier` accepts empty signing secret without precondition
SecretsVerifier in slack-go/slack before v0.23.1 accepts an empty signing secret without error. If an application is misconfigured (e.g., an unset or empty SLACK_SIGNING_SECRET), NewSecretsVerifier builds an HMAC-SHA256 keyed with an empty string, allowing an unauthenticated attacker to forge a valid X-Slack-Signature and bypass Slack request authentication. Fixed in v0.23.1, which rejects empty secrets with ErrInvalidConfiguration. This is patched in version 0.23.1.
- Record
GHSA-gxhx-2686-5h9g- CVSS 4.0
- 4.8 Medium
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N/E:U - Weakness
- CWE-287, CWE-326, CWE-1391
- Updated
- 2026-11-02
OSV
slack-go `SecretsVerifier` accepts empty signing secret without precondition
SecretsVerifier in slack-go/slack before v0.23.1 accepts an empty signing secret without error. If an application is misconfigured (e.g., an unset or empty SLACK_SIGNING_SECRET), NewSecretsVerifier builds an HMAC-SHA256 keyed with an empty string, allowing an unauthenticated attacker to forge a valid X-Slack-Signature and bypass Slack request authentication. Fixed in v0.23.1, which rejects empty secrets with ErrInvalidConfiguration. This is patched in version 0.23.1.
- Record
GHSA-gxhx-2686-5h9g- CVSS 4.0
- 4.8 Medium
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N/E:U - Weakness
- CWE-1391, CWE-287, CWE-326
- Updated
- 2026-11-02
OSVGO-2026-5410No score
SecretsVerifier accepts empty signing secret without precondition in github.com/slack-go/slack
SecretsVerifier accepts empty signing secret without precondition in github.com/slack-go/slack
- Record
GO-2026-5410- Updated
- 2026-11-02
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | GitHub Advisories, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.