CVE-2026-56104: chainlit · Missing Authorization
Affects chainlitSource CVE Database V5
Not known to be exploited · CVSS 8.8 High : upgrade to 2.10.1 soon.
Data as of 8 Nov 2026, 14:34 UTC
Thin evidence
One scorer or none| CNA (VulnCheck) | CVSS 4.0 | 8.8 |
|---|---|---|
| CNA (VulnCheck) | CVSS 3.1 | 8.2 |
- CISA SSVC
- Exploitation
- No evidence of active exploitation and no public proof of concept
- Automatable
- Attackers cannot reliably automate steps 1–4 of the kill chain
- Technical impact
- Total control over the software or total information disclosure
CISA SSVC assessment, 2026-06-22.
- Patch
- Available – fixed in 2.10.1
CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:H/SI:H/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 22 Jun 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 8 Nov 2026.
What to do
Upgrade chainlit to 2.10.1.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Chainlitchainlit | Affected
| Fixed in– |
PyPIchainlitpkg:pypi/chainlitOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
Description
Chainlit before 2.10.1 contains a session hijacking vulnerability that allows unauthenticated attackers to restore and inherit authenticated user sessions by presenting a valid sessionId during WebSocket session restoration without ownership verification. Attackers can exploit the restore_existing_session path to assume a victim's permissions and roles, enabling unauthorized invocation of tools and access to data restricted to the authenticated victim.
References
- github.com/Chainlit/chainlit/releases/tag/2.10.1 (opens in a new tab)
- github.com/Chainlit/chainlit/pull/2857 (opens in a new tab)
- github.com/Chainlit/chainlit/commit/5effb664f1e0af4a4f0a42fe63ea979676039a7f (opens in a new tab)
- vulncheck.com/advisories/chainlit-session-hijacking-via-websocket-session-restoration (opens in a new tab)