CVE-2026-34840 details an authentication bypass vulnerability in OneUptime's SAML Single Sign-On (SSO) implementation, affecting versions prior to 10.0.42. The flaw arises from decoupled signature verification and identity extraction, allowing an attacker to prepend an unsigned assertion with an arbitrary identity before a legitimately signed one. Rated 8.1 High on the CVSS scale, this vulnerability has a network attack vector, low attack complexity, and can lead to high impacts on confidentiality and integrity. Exploitation requires low privileges and no user interaction. There is currently no evidence of active exploitation, nor are public exploit codes available, though it has garnered minor community discussion.
| Vendor | Product | Version(s) | CPE |
|---|---|---|---|
< 10.0.42CPE matchmatch criteria | cpe:2.3:a:hackerbay:oneuptime:*:*:*:*:*:*:*:* |
CVSS version used by this source: 3.1
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
The average CVE in this peer group has 0.0 Twitter, 0.0 Reddit, 0.3 Bluesky, 0.1 Mastodon, and 0.2 GitHub mentions.
No media coverage found for this CVE.
The average CVE in this peer group has 0.1 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.