CVE-2026-55536 json
Browser Server WebSocket origin validation bypass via unanchored regex (patch bypass of CVE-2026-40289 / GHSA-8x8f-54wf-vv92)
published 2026-08-25 2 mo ago modified 2026-09-10 1 mo ago also EUVD-2026-65545 , GHSA-6g6r-q6gw-w8fg , PYSEC-2026-3886
- cvss
- 9.1
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 44%
- public exploits
- 0
- none known
Summary
PraisonAI is a multi-agent teams system. Prior to praisonai 4.6.58, Browser Server _handle_connection() checks Chrome extension origins with re.match() and the unanchored expression chrome-extension://[a-z0-9]{32}. Extra trailing characters pass before websocket.accept(), allowing start_session commands and unauthorized browser automation. This issue is fixed in version 4.6.58.
Patch / fix
- pypi praisonai 4.6.58
- praison praisonai 4.6.58
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- no
- Technical impact
- total
- Assessed
- 2 mo ago
Exploit prediction
0.52% chance of exploitation in the next 30 days, higher than 44% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- github.com https://github.com/MervinPraison/PraisonAI/security/advisories/GHSA-6g6r-q6gw-w8fg referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 9.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N |
| GitHub | 3.1 | 9.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N |
| OSV | 3.1 | 9.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| pypi | praisonai | <4.6.58 |
4.6.58 |
Affected products
- MervinPraison PraisonAI
Classification
References
-
github.com
/MervinPraison/PraisonAI/commit/2f9677abb2ea68eab864ee8b6a828fd0141612e1
web
-
github.com
/MervinPraison/PraisonAI/security/advisories/GHSA-6g6r-q6gw-w8fg
exploit, web
-
github.com
/MervinPraison/PraisonAI/releases/tag/v4.6.58
web
-
github.com
/MervinPraison/PraisonAI
package
-
pypi.org
/project/praisonai
package
-
github.com
/advisories/GHSA-6g6r-q6gw-w8fg
advisory
-
nvd.nist.gov
/vuln/detail/CVE-2026-55536
advisory
Sources
- CVE List CVE-2026-55536
- GitHub Advisory GHSA-6g6r-q6gw-w8fg
- NVD CVE-2026-55536
- OSV PYSEC-2026-3886
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.