IBM DataPower Gateway: Out-of-bounds write in RFC2047 encoded-word parser
Summary
IBM DataPower Gateway versions 10.5.0.0 to 10.5.0.22, 10.6.1 to 10.6.6, 10.6.0.0 to 10.6.0.10 and 11.0.0.0 to 11.0.0.2 contain an out-of-bounds write in the RFC2047 encoded-word parser. A remote attacker can exploit this without authentication or user interaction to execute arbitrary code on the gateway. The CVSS score is 9.8 (critical); the exact feature and input are not described by the vendor.
Affected
- IBM DataPower Gateway 10.5.0.0 to 10.5.0.22
- IBM DataPower Gateway 10.6.1 to 10.6.6 (10.6CD)
- IBM DataPower Gateway 10.6.0.0 to 10.6.0.10
- IBM DataPower Gateway 11.0.0.0 to 11.0.0.2
Fixed in
- 10.5.0 branch: 10.5.0.23
- 10.6.0 branch: 10.6.0.11
- 11.0.0 branch: 11.0.0.3
- 10.6CD branch (10.6.1 to 10.6.6): 11.0.0.3 according to the CVE record table; verify the exact target in the IBM bulletin before patching
Workaround
No official workaround documented.
- Restrict management and service ports to trusted networks.
- Limit which systems can reach the gateway from the internet.
Exploitation
- No evidence of exploitation in the wild; CISA SSVC lists exploitation as none.
- No public proof of concept found.
- EPSS 0.00489 at the time of the snapshot.
- Automatable: yes according to CISA SSVC.
Our recommendation
- Inventory all DataPower instances, including development, DMZ and partner-managed systems.
- Check each instance's version against the IBM bulletin and install the applicable fixed release for its branch.
- Patch this CVE together with the other DataPower fixes released in the same IBM bulletin.
- Isolate unpatched gateways from the internet until patched.
- Monitor the gateway for unusual process activity or crashes.
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- IBM Security Bulletin (node 7289775) www.ibm.com
- IBM Security Bulletin: IBM DataPower Gateway affected by multiple CVEs www.ibm.com
- VulDB entry for CVE-2026-16340 vuldb.com
- HOL Guard CVE summary hol.org
- Strix CVE summary www.strix.ai
- ThreatInt NVD data cve.threatint.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 30 Oct 2026, 20:32.
Original description (NVD)
IBM DataPower Gateway 10.5.0.0 through 10.5.0.22, 10.6.1 through 10.6.6, 10.6.0.0 through 10.6.0.10, and 11.0.0.0 through 11.0.0.2 could allow a remote attacker to execute arbitrary code due to an out-of-bounds write in the RFC2047 encoded-word parser.
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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