Adobe Connect: CRLF injection leading to code execution
Summary
Adobe Connect contains a CRLF injection vulnerability (CWE-93, CVE-2026-121353) with a CVSS score of 10.0. According to the CVE record, an unauthenticated remote attacker can exploit it without user interaction and with a changed scope, which may allow code execution in the context of the current user and control over the victim's account or session. The Adobe bulletin APSB26-191 addresses this issue together with other critical and high vulnerabilities in the same release.
Affected
- Adobe Connect 0 to 12.8 (fixed in 12.8.a)
- Adobe Connect 0 to 12.9 (fixed in 12.9.a)
- Adobe Connect 0 to 12.10 (fixed in 12.10.f)
- Adobe Connect 0 to 12.11 (fixed in 12.11.i)
- Adobe Connect 12.12: unknown, to be verified in APSB26-191
- Platform according to the bulletin: Windows
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 (per bulletin table; applicability to this CVE to be verified)
Workaround
Unknown. No vendor-specific workaround was identified for this CVE.
Exploitation
- Adobe is not aware of any exploits in the wild for the issues in APSB26-191.
- No public proof of concept has been identified so far; the CVE was published on 2026-11-10.
- Exploitation requires no privileges and no user interaction over the network.
Our recommendation
- Check whether Adobe Connect is in use and which version and branch is installed.
- Check whether the Connect server is reachable from the internet and restrict access to known users and networks until patched.
- Read APSB26-191 to confirm the exact affected and fixed builds and install the update as a priority.
- Monitor for public proof of concept and exploitation reports and re-check after 24 to 48 hours.
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-2026-121353 www.cve.org
- Zero Day Initiative: November 2026 Security Update Review www.zerodayinitiative.com
- OffSeq Radar: CVE-2026-121353 radar.offseq.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 10 Nov 2026, 23:21.
Original description (NVD)
Adobe Connect is affected by an Improper Neutralization of CRLF Sequences ('CRLF Injection') vulnerability that could result in arbitrary code execution in the context of the current user, potentially gaining elevated access or control over the victim's account or session. 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.
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