Gentoo update for Bash
| Risk | Critical |
| Patch available | YES |
| Number of vulnerabilities | 4 |
| CVE-ID | CVE-2014-6277 CVE-2014-7186 CVE-2014-7187 CVE-2014-6278 |
| CWE-ID | CWE-119 CWE-193 CWE-77 |
| Exploitation vector | Network |
| Public exploit |
Vulnerability #1 is being exploited in the wild. Vulnerability #2 is being exploited in the wild. Vulnerability #3 is being exploited in the wild. Vulnerability #4 is being exploited in the wild. |
| Vulnerable software |
Gentoo Linux Operating systems & Components / Operating system |
| Vendor | Gentoo |
Security Bulletin
This security bulletin contains information about 4 vulnerabilities.
1) Memory corruption
EUVDB-ID: #VU5310
Risk: Critical
CVSSv4.0: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:A/U:Red]
CVE-ID: CVE-2014-6277
CWE-ID:
CWE-119 - Memory corruption
Exploit availability: Yes
DescriptionThe vulnerability allows a remote attacker to execute arbitrary code on the target system.
The vulnerability exists due to incorrect parsing of environment variables. A remote attacker can trigger memory corruption and execute arbitrary code on the target system as demonstrated by vectors involving the ForceCommand feature in OpenSSH sshd, the mod_cgi and mod_cgid modules in the Apache HTTP Server, scripts executed by unspecified DHCP clients, and other situations in which setting the environment occurs across a privilege boundary from Bash execution. The vulnerability was introduced by incorrect patching of vulnerabilities #1 (CVE-2014-6271) and #2 (CVE-2014-7169).
Successful exploitation results in arbitrary code execution on the vulnerable system.
Note: this vulnerability was being actively exploited in the wild.
Mitigation
Update the affected packages.
app-shells/bash to version:
Gentoo Linux: All versions
CPE2.3 External linkshttps://security.gentoo.org/glsa/201410-01
Q & A
Can this vulnerability be exploited remotely?
Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.
Is there known malware, which exploits this vulnerability?
No. We are not aware of malware exploiting this vulnerability. However, a fully functional exploit for this vulnerability is available.
2) Memory corruption
EUVDB-ID: #VU5327
Risk: Critical
CVSSv4.0: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:A/U:Red]
CVE-ID: CVE-2014-7186
CWE-ID:
CWE-119 - Memory corruption
Exploit availability: Yes
DescriptionThe vulnerability allows a remote attacker to execute arbitrary code on the target system.
The weakness exists due to out-of-bounds memory access while handling multiple "<<EOF" declarations. A remote attacker can trigger memory corruption and execute arbitrary code.
Exploitation example:
bash -c 'true <<EOF <<EOF <<EOF <<EOF <<EOF <<EOF <<EOF <<EOF <<EOF <<EOF <<EOF <<EOF <<EOF <<EOF' || echo "CVE-2014-7186 vulnerable, redir_stack"
Successful exploitation results in arbitrary code execution on the vulnerable system.
Note: this vulnerability was being actively exploited.
Mitigation
Update the affected packages.
app-shells/bash to version:
Gentoo Linux: All versions
CPE2.3 External linkshttps://security.gentoo.org/glsa/201410-01
Q & A
Can this vulnerability be exploited remotely?
Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.
Is there known malware, which exploits this vulnerability?
No. We are not aware of malware exploiting this vulnerability. However, a fully functional exploit for this vulnerability is available.
3) Off-by-one error
EUVDB-ID: #VU5328
Risk: Critical
CVSSv4.0: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:A/U:Red]
CVE-ID: CVE-2014-7187
CWE-ID:
CWE-193 - Off-by-one Error
Exploit availability: Yes
DescriptionThe vulnerability allows a remote attacker to execute arbitrary code on the target system.
The weakness exists due to off-by-one-error when handling deeply nested flow control constructs. A remote attacker can trigger memory corruption and execute arbitrary code with privileges of the current user.
Exploitation example:
(for x in {1..200} ; do echo "for x$x in ; do :"; done; for x in {1..200} ; do echo done ; done) | bash ||
echo "CVE-2014-7187 vulnerable, word_lineno"
Successful exploitation results in arbitrary code execution on the vulnerable system.
Note: this vulnerability was being actively exploited.
Mitigation
Update the affected packages.
app-shells/bash to version:
Gentoo Linux: All versions
CPE2.3 External linkshttps://security.gentoo.org/glsa/201410-01
Q & A
Can this vulnerability be exploited remotely?
Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.
Is there known malware, which exploits this vulnerability?
No. We are not aware of malware exploiting this vulnerability. However, a fully functional exploit for this vulnerability is available.
4) Command injection
EUVDB-ID: #VU5322
Risk: Critical
CVSSv4.0: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:A/U:Red]
CVE-ID: CVE-2014-6278
CWE-ID:
CWE-77 - Command injection
Exploit availability: Yes
DescriptionThe vulnerability allows a remote attacker to execute arbitrary code on the target system.
The weakness exists due to an incomplete fix related to the parsing of user scripts. By using attack vectors involving the ForceCommand feature in OpenSSH sshd, the mod_cgi and mod_cgid modules in the Apache HTTP Server, a remote attacker can execute arbitrary code with privileges of the current user. The vulnerability was introduced by incorrect patching of vulnerabilities #1 (CVE-2014-6271), #2 (CVE-2014-7169) and #3 (CVE-2014-6277)
Successful exploitation results in arbitrary code execution on the vulnerable system.
Note: this vulnerability was being actively exploited.
Mitigation
Update the affected packages.
app-shells/bash to version:
Gentoo Linux: All versions
CPE2.3 External linkshttps://security.gentoo.org/glsa/201410-01
Q & A
Can this vulnerability be exploited remotely?
Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.
Is there known malware, which exploits this vulnerability?
No. We are not aware of malware exploiting this vulnerability. However, a fully functional exploit for this vulnerability is available.
