Adobe Connect: XML External Entity injection allows arbitrary file read
Summary
Adobe Connect contains an XML External Entity (XXE) injection flaw (CWE-611) that allows reading files outside the intended scope on the server. An authenticated attacker with low privileges can exploit it without user interaction, and the CVSS vector indicates a scope change. Confidentiality is highly affected, while integrity and availability are not. Adobe classifies the flaw as part of its November 2026 update APSB26-191, which is rated priority 2.
Affected
- Adobe Connect 0 through 12.8, 12.9, 12.10 and 12.11 (per CVE record, Windows)
- Adobe Connect 12.12: unknown until verified against the advisory APSB26-191
- Version details must be checked against the vendor advisory before acting
Fixed in
- Adobe Connect 12.8.a
- Adobe Connect 12.9.a
- Adobe Connect 12.10.f
- Adobe Connect 12.11.i
- Adobe Connect 12.12.a (listed in APSB26-191 as updated version; affected status of 12.12 unverified)
Workaround
Unknown. No vendor-documented workaround is known; patching is the primary fix.
Exploitation
- Not known to be exploited (per OffSeq and ZDI)
- Adobe is not aware of any exploits in the wild for the issues in APSB26-191
- No public proof of concept found; this is not proof that none exists
Our recommendation
- Check the Adobe Connect version against advisory APSB26-191 and update to the fixed build
- Apply the whole APSB26-191 bulletin, not only this CVE
- Prioritise internet-facing Connect servers and restrict access to required networks
- Review which user accounts exist and whether self-registration is enabled
- Monitor for unusual file access on the server
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- Adobe Security Bulletin APSB26-191 www.adobe.com
- CVE Record CVE-2026-121890 www.cve.org
- OffSeq Radar CVE-2026-121890 radar.offseq.com
- Strix CVE-2026-121890 www.strix.ai
- Threatint CVE-2026-121890 cve.threatint.com
- HKCERT Adobe security update November 2026 www.hkcert.org
- ZDI November 2026 security update review www.zerodayinitiative.com
Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 11 Nov 2026, 04:43.
Original description (NVD)
Adobe Connect is affected by an Improper Restriction of XML External Entity Reference ('XXE') vulnerability that could lead to arbitrary file system read. A low-privileged attacker could exploit this vulnerability to access sensitive files and directories outside the intended access scope. Exploitation of this issue does not require user interaction. Scope is changed.
NVD references (1)
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
Affected? We can help.
We check whether your systems are affected, install updates and close the gap – continuously with the System Health Checker if you wish.