Multiple vulnerabilities in Lua
Security Bulletin
This security bulletin contains information about 4 vulnerabilities.
Updated: 19.11.2020
Added vulnerabilities #3-4.
1) Out-of-bounds read
EUVDB-ID: #VU47701
Risk: Medium
CVSSv4.0: 2.1 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]
CVE-ID: CVE-2020-15889
CWE-ID:
CWE-125 - Out-of-bounds read
Exploit availability: No
DescriptionThe vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to getobjname heap-based buffer over-read within the youngcollection() function in lgc.c that uses markold for an insufficient number of list members. A remote attacker can perform a denial of service attack.
MitigationInstall update from vendor's website.
Vulnerable software versionsLua: 5.4.0
CPE2.3 External linkshttps://lua-users.org/lists/lua-l/2020-07/msg00078.html
https://github.com/lua/lua/commit/127e7a6c8942b362aa3c6627f44d660a4fb75312
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.
2) Heap-based buffer overflow
EUVDB-ID: #VU47700
Risk: Medium
CVSSv4.0: 4.8 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]
CVE-ID: CVE-2020-15888
CWE-ID:
CWE-122 - Heap-based Buffer Overflow
Exploit availability: No
DescriptionThe vulnerability allows a remote attacker to execute arbitrary code on the target system.
The vulnerability exists due to a boundary error during interaction between stack resizes and garbage collection in ldo.c file. A remote attacker can pass specially crafted data to the application, trigger heap-based buffer overflow and execute arbitrary code on the target system.
Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.
MitigationInstall updates from vendor's website.
Vulnerable software versionsLua: 5.2.0 - 5.4.0
CPE2.3- cpe:2.3:a:lua:lua:5.2.0:*:*:*:*:*:*:*
- cpe:2.3:a:lua:lua:5.2.1:*:*:*:*:*:*:*
- cpe:2.3:a:lua:lua:5.2.2:*:*:*:*:*:*:*
https://lua-users.org/lists/lua-l/2020-07/msg00053.html
https://lua-users.org/lists/lua-l/2020-07/msg00054.html
https://lua-users.org/lists/lua-l/2020-07/msg00071.html
https://lua-users.org/lists/lua-l/2020-07/msg00079.html
https://github.com/lua/lua/commit/6298903e35217ab69c279056f925fb72900ce0b7
https://github.com/lua/lua/commit/eb41999461b6f428186c55abd95f4ce1a76217d5
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.
3) Memory corruption
EUVDB-ID: #VU48558
Risk: Medium
CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]
CVE-ID: CVE-2020-15945
CWE-ID:
CWE-119 - Memory corruption
Exploit availability: No
DescriptionThe vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to a segmentation fault in changedline in ldebug.c (e.g., when called by
luaG_traceexec) because it incorrectly expects that an oldpc value is
always updated upon a return of the flow of control to a function. A remote attacker can pass specially crafted data to the application and crash it.
Install updates from vendor's website.
Vulnerable software versionsLua: 5.2.0 - 5.4.0
CPE2.3- cpe:2.3:a:lua:lua:5.2.0:*:*:*:*:*:*:*
- cpe:2.3:a:lua:lua:5.2.1:*:*:*:*:*:*:*
- cpe:2.3:a:lua:lua:5.2.2:*:*:*:*:*:*:*
https://lua-users.org/lists/lua-l/2020-07/msg00123.html
https://github.com/lua/lua/commit/a2195644d89812e5b157ce7bac35543e06db05e3
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.
4) Buffer overflow
EUVDB-ID: #VU48559
Risk: High
CVSSv4.0: 6.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]
CVE-ID: CVE-2020-24342
CWE-ID:
CWE-119 - Memory corruption
Exploit availability: No
DescriptionThe vulnerability allows a remote attacker to execute arbitrary code on the target system.
The vulnerability exists due to a stack redzone cross in luaO_pushvfstring because a protection mechanism wrongly calls luaD_callnoyield twice in a row. A remote attacker can pass specially crafted data to the application, trigger memory corruption and execute arbitrary code on the target system.
Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.
MitigationInstall updates from vendor's website.
Vulnerable software versionsLua: 5.4.0
CPE2.3 External linkshttps://lua-users.org/lists/lua-l/2020-07/msg00052.html
https://github.com/lua/lua/commit/34affe7a63fc5d842580a9f23616d057e17dfe27
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.
