CVE-2011-4879

CVE-2011-4879 is a high-severity vulnerability in Siemens Wincc Flexible with a CVSS 2.0 base score of 8.5. Its EPSS exploit-prediction score of 13% places it in the 96th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-20.

Key facts

• Severity: High (CVSS 2.0 base score 8.5)
• EPSS exploit prediction: 13% (96th percentile)
• Actively exploited: Not listed in CISA KEV
• Weakness: CWE-20
• Affected product: Siemens Wincc Flexible
• Published: 2012-02-03
• Last modified: 2026-06-16

Description

miniweb.exe in the HMI web server in Siemens WinCC flexible 2004, 2005, 2007, and 2008 before SP3; WinCC V11 (aka TIA portal) before SP2 Update 1; the TP, OP, MP, Comfort Panels, and Mobile Panels SIMATIC HMI panels; WinCC V11 Runtime Advanced; and WinCC flexible Runtime does not properly handle URIs beginning with a 0xfa character, which allows remote attackers to read data from arbitrary memory locations or cause a denial of service (application crash) via a crafted POST request.

Frequently asked questions

What is CVE-2011-4879?

miniweb.exe in the HMI web server in Siemens WinCC flexible 2004, 2005, 2007, and 2008 before SP3; WinCC V11 (aka TIA portal) before SP2 Update 1; the TP, OP, MP, Comfort Panels, and Mobile Panels SIMATIC HMI panels; WinCC V11 Runtime Advanced; and WinCC flexible Runtime does not properly handle URIs beginning with a 0xfa character, which allows remote attackers to read data from arbitrary memory locations or cause a denial of service (application crash) via a crafted POST request.

How severe is CVE-2011-4879?

CVE-2011-4879 has a CVSS 2.0 base score of 8.5, rated high severity.

Is CVE-2011-4879 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 13% (96th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2011-4879?

CVE-2011-4879 primarily affects Siemens Wincc Flexible. In total, 16 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2011-4879?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2011-4879 published?

CVE-2011-4879 was published on 2012-02-03 and last updated on 2026-06-16.

References

• http://aluigi.org/adv/winccflex_1-adv.txt
• http://www.exploit-db.com/exploits/18166
• http://www.osvdb.org/77384
• http://www.siemens.com/corporate-technology/pool/de/forschungsfelder/siemens_security_advisory_ssa-345442.pdf
• http://www.us-cert.gov/control_systems/pdf/ICS-ALERT-11-332-02.pdf
• http://www.us-cert.gov/control_systems/pdf/ICS-ALERT-11-332-02A.pdf
• http://www.us-cert.gov/control_systems/pdf/ICSA-12-030-01.pdf
• https://exchange.xforce.ibmcloud.com/vulnerabilities/71453

Affected products (16)

• cpe:2.3:a:siemens:wincc_flexible:2004:*:*:*:*:*:*:*
• cpe:2.3:a:siemens:wincc_flexible:2005:*:*:*:*:*:*:*
• cpe:2.3:a:siemens:wincc_flexible:2007:*:*:*:*:*:*:*
• cpe:2.3:a:siemens:wincc_flexible:2008:*:*:*:*:*:*:*
• cpe:2.3:a:siemens:wincc_flexible:2008:sp1:*:*:*:*:*:*
• cpe:2.3:a:siemens:wincc_flexible:2008:sp2:*:*:*:*:*:*
• cpe:2.3:a:siemens:wincc:*:sp2:*:*:*:*:*:*
• cpe:2.3:a:siemens:wincc:v11:*:*:*:*:*:*:*
• cpe:2.3:a:siemens:wincc:v11:sp1:*:*:*:*:*:*
• cpe:2.3:a:siemens:simatic_hmi_panels:comfort_panels:*:*:*:*:*:*:*
• cpe:2.3:a:siemens:simatic_hmi_panels:mobile_panels:*:*:*:*:*:*:*
• cpe:2.3:a:siemens:simatic_hmi_panels:mp:*:*:*:*:*:*:*
• cpe:2.3:a:siemens:simatic_hmi_panels:op:*:*:*:*:*:*:*
• cpe:2.3:a:siemens:simatic_hmi_panels:tp:*:*:*:*:*:*:*
• cpe:2.3:a:siemens:wincc_runtime_advanced:v11:*:*:*:*:*:*:*
• cpe:2.3:a:siemens:wincc_flexible_runtime:*:*:*:*:*:*:*:*

More vulnerabilities in Siemens Wincc Flexible

• CVE-2011-4514 — Critical (CVSS 10.0): The TELNET daemon in Siemens WinCC flexible 2004, 2005, 2007, and 2008; WinCC V11 (aka TIA portal); the TP, OP, MP,…
• CVE-2011-4513 — Critical (CVSS 10.0): Siemens WinCC flexible 2004, 2005, 2007, and 2008; WinCC V11 (aka TIA portal); the TP, OP, MP, Comfort Panels, and…
• CVE-2011-4509 — Critical (CVSS 10.0): The HMI web server in Siemens WinCC flexible 2004, 2005, 2007, and 2008; WinCC V11 (aka TIA portal); the TP, OP, MP,…
• CVE-2011-4876 — Critical (CVSS 9.3): Directory traversal vulnerability in HmiLoad in the runtime loader in Siemens WinCC flexible 2004, 2005, 2007, and…
• CVE-2011-4875 — Critical (CVSS 9.3): Stack-based buffer overflow in HmiLoad in the runtime loader in Siemens WinCC flexible 2004, 2005, 2007, and 2008;…
• CVE-2011-4508 — Critical (CVSS 9.3): The HMI web server in Siemens WinCC flexible 2004, 2005, 2007, and 2008 before SP3; WinCC V11 (aka TIA portal) before…

All CVEs affecting Siemens Wincc Flexible →

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