Predictive Vulnerability Intelligence.

Product

  • Product
  • Pricing
  • Documentation

Company

  • About
  • Partnerships
  • Blog
  • Support

Legal

  • Terms
  • Privacy
  • Data Licensing

© 2026 FAUCET Technologies LLC. All rights reserved.

CVE-2011-4577

21
FAUCET Score

CVE-2011-4577 describes a denial-of-service vulnerability in OpenSSL versions prior to 0.9.8s and 1.0.0f, specifically when RFC 3779 support is enabled. Attackers can trigger an assertion failure by providing a specially crafted X.509 certificate containing malformed IP address blocks or Autonomous System identifiers. This vulnerability has a CVSS score of 4.3, indicating a medium attack complexity and potential for partial denial of service, but no impact on confidentiality or integrity. There is no evidence of active exploitation, public exploit code, or significant community discussion surrounding this CVE.

Impacted Technologies

VendorProductVersion(s)CPE
<= 0.9.8rCPE matchmatch criteria
cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*
0.9.1cCPE matchmatch criteria
cpe:2.3:a:openssl:openssl:0.9.1c:*:*:*:*:*:*:*
0.9.2bCPE matchmatch criteria
cpe:2.3:a:openssl:openssl:0.9.2b:*:*:*:*:*:*:*
0.9.4CPE matchmatch criteria
cpe:2.3:a:openssl:openssl:0.9.4:*:*:*:*:*:*:*
0.9.5CPE matchmatch criteria
cpe:2.3:a:openssl:openssl:0.9.5:*:*:*:*:*:*:*

CVSS Data

CVSS version used by this source: 2.0

4.3MEDIUM

AV:N/AC:M/Au:N/C:N/I:N/A:P

Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
PARTIAL
Access Vector
NETWORK
Access Complexity
MEDIUM
Authentication
NONE
Exploitability Score
8.6
Impact Score
2.9
CvssVersion
2.0

Exploit Intelligence

EPSS Score
9.33%
Probability of exploitation in next 30 days
EPSS Percentile
94.9%
Percentile rank of EPSS score among Peer Group
As of 2026-07-24
Model: v2026.06.15
This CVE's current EPSS score of 0.0933 is in the 94th percentile among its peer group of 19,953 CVEs.

Social Chatter

The average CVE in this peer group has 0.0 Twitter, 0.0 Reddit, 0.0 Bluesky, 0.0 Mastodon, and 0.2 GitHub mentions.

Media Mentions

No media coverage found for this CVE.

The average CVE in this peer group has 0.0 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.

Remediation

Patch Available

Vendor Patches (2)

redhatpatch availablevia redhat_api
Product: Red Hat Enterprise Linux 6Fixed in: openssl-0:1.0.0-20.el6_2.1
View patch
redhatpatch availablevia redhat_api
Product: RHEV 3.X Hypervisor and Agents for RHEL-6Fixed in: rhev-hypervisor6-0:6.2-20120209.0.el6_2
View patch

Vendor Advisories (1)

redhatCVE-2011-4577Moderate

openssl: malformed RFC 3779 data can cause assertion failures

Jan 4, 2012

References

h20000.www2.hp.com / bizsupport/TechSupport/Document.jsp
lists.apple.com / archives/security-announce/2013/Jun/msg00000.html
lists.fedoraproject.org / pipermail/package-announce/2012-November/092905.html
lists.opensuse.org / opensuse-security-announce/2012-01/msg00017.html
lists.opensuse.org / opensuse-security-announce/2012-01/msg00018.html
marc.info
marc.info
secunia.com / advisories/57353
support.apple.com / kb/HT5784
www-01.ibm.com / support/docview.wss
kb.cert.org / vuls/id/737740
US Government Resource
openssl.org / news/secadv_20120104.txt