CVE-2012-6066Freesshd Authentication Bypass
freeSSHd.exe in freeSSHd through 1.2.6 allows remote attackers to bypass authentication via a crafted session, as demonstrated by an OpenSSH client with modified versions of ssh.c and sshconnect2.c.
Published Dec 4, 2012 · Updated Apr 28, 2026
Key Facts
Patch immediately- CVE-2012-6066 is a critical-severity vulnerability (CVSS 9.3 v2) affecting Freesshd.
- It is not listed in any known-exploited vulnerabilities catalog. Public exploit code is available.
- EPSS estimates a 40% probability of exploitation in the next 30 days.
- Fixed versions are available, including Freesshd 1.2.6.
- Brandefense priority: patch immediately, because public exploit code exists for a high-severity flaw.
Scores
CVSS v2
9.3
AV:N/AC:M/Au:N/C:C/I:C/A:C
EPSS (30-day exploit likelihood)
40%
Higher than 98.5% of all scored CVEs
Exploit maturity
Weaponized
ATLAS score
56/100
Publication score, see How it works
Exploitation Verdict
KEV listed
Not listed
Federal due date
None
No federal due date
Ransomware use
Not reported
Attributed actors
None named
Exploit & Defence Guidance
Exploit maturity
Weaponized
Public exploit code
4
Proof-of-concept links
In-the-wild evidence
0
Reports of active use
Description
freeSSHd.exe in freeSSHd through 1.2.6 allows remote attackers to bypass authentication via a crafted session, as demonstrated by an OpenSSH client with modified versions of ssh.c and sshconnect2.c.
Affected Products
3 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| FreesshdFreesshd | 1.2.1, 1.2.2 | 1.2.6 |
Patched Releases
Freesshd
1.2.6
Timeline
Publicly disclosed
Dec 4, 2012
Last updated
Apr 28, 2026
Weakness Type
- CWE-287 Improper Authentication
References
FAQ
Common Questions.
freeSSHd.exe in freeSSHd through 1.2.6 allows remote attackers to bypass authentication via a crafted session, as demonstrated by an OpenSSH client with modified versions of ssh.c and sshconnect2.c.
Affected: Freesshd versions 1.2.1, 1.2.2. The full list is in the CVE brief.
It is not listed in any known-exploited vulnerabilities catalog.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
Public exploit code is available.
Fixed versions are available, including Freesshd 1.2.6.
Brandefense priority: patch immediately, because public exploit code exists for a high-severity flaw.
Is CVE-2012-6066 On Your Attack Surface?
Brandefense matches it against the products discovered on your perimeter and opens a finding the day a CVE like this is listed.
Request A Demo