SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityDeferred

CVE-2026-61687

Prior to 0.91.1, ValidateOAuthState clears the oauth_state_ session value to an empty string after a successful OAuth callback and later accepts an empty state parameter as equal, allowing an unauthenticated attacker to bind a victim's Hatchet session…

HIGH 7.1EPSS 0.17%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.17%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

Hatchet is a platform for orchestrating background tasks, AI agents, and durable workflows at scale. Prior to 0.91.1, ValidateOAuthState clears the oauth_state_ session value to an empty string after a successful OAuth callback and later accepts an empty state parameter as equal, allowing an unauthenticated attacker to bind a victim's Hatchet session to an attacker-controlled OAuth identity. Exploitation requires the victim to have completed an OAuth flow in the current session and the deployment to enable auth.google.enabled, auth.github.enabled, or the Slack integration. This issue is fixed in version 0.91.1.

CVSS 3.1
7.1 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:H/A:N
EPSS
0.17% probability · 6th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-287, CWE-352, CWE-384, CWE-1275
Source
security-advisories@github.com
EPSS trend
0%3%5%22 September 2026: 0.12%26 October 2026: 0.17%22 September 202626 October 2026

EPSS moved from 0.1% on 22 September 2026 to 0.2% on 26 October 2026.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.