SB2017081719 - Amazon Linux AMI update for php56
Published: August 17, 2017
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 5 vulnerabilities.
1) Heap-out-of-bounds write (CVE-ID: CVE-2017-9228)
CWE-ID: CWE-787 - Out-of-bounds write
CVSSv4: 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:U/U:Amber
The vulnerability allows a remote attacker to execute arbitrary code.
The weakness exists in the mbstring due to heap out-of-bounds write in bitset_set_range() during regular expression compilation due to incorrect state transition in parse_char_class(). A remote attacker can trigger out-of-bounds write memory corruption and execute arbitrary code with web server privileges.
Successful exploitation of the vulnerability may result in system compromise.
2) Null pointer dereference (CVE-ID: CVE-2017-9229)
CWE-ID: CWE-476 - NULL Pointer Dereference
CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Clear
The vulnerability allows a remote attacker to cause DoS condition.
The weakness exists in the mbstring due to an error in handling of reg->dmin in forward_search_range(). A remote attacker can trigger SIGSEGV in left_adjust_char_head() during regular expression compilation, cause NULL pointer dereference and the application to crash.
Successful exploitation of the vulnerability results in denial of service.
3) Heap-out-of-bounds write (CVE-ID: CVE-2017-9226)
CWE-ID: CWE-787 - Out-of-bounds write
CVSSv4: 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:U/U:Amber
The vulnerability allows a remote attacker to execute arbitrary code.
The weakness exists in the mbstring due to heap out-of-bounds write or read occurs in next_state_val() during regular expression compilation. A remote attacker can supply a malformed regular expression containing an octal number in the form of '\700', trigger
out-of-bounds write memory corruption and execute arbitrary code with web server privileges.
Successful exploitation of the vulnerability may result in system compromise.
4) Out-of-bounds read (CVE-ID: CVE-2017-9227)
CWE-ID: CWE-125 - Out-of-bounds read
CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
The vulnerability allows a remote attacker to obtain potentially sensitive information.
The weakness exists in the mbstring due to an error in handling of reg->dmin in forward_search_range(). A remote attacker can trigger stack out-of-bounds read in mbc_enc_len() during regular expression searching and read arbitrary files on the system.
Successful exploitation of the vulnerability results in information disclosure.
5) Out-of-bounds read (CVE-ID: CVE-2017-9224)
CWE-ID: CWE-125 - Out-of-bounds read
CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
The vulnerability allows a remote attacker to obtain potentially sensitive information.
The weakness exists in the mbstring due to stack out-of-bounds read in match_at() during regular expression searching. A remote attacker can trigger a logical error involving order of validation and access in match_at() and read arbitrary files on the system.
Successful exploitation of the vulnerability results in information disclosure.
Remediation
Install update from vendor's website.