SB2020082504 - Multiple vulnerabilities in Lua

Description

This security bulletin contains information about 3 secuirty vulnerabilities.

1) NULL pointer dereference (CVE-ID: CVE-2020-24369)

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to a NULL pointer dereference error. A remote attacker can trigger denial of service conditions via the line hook of a stripped function, leading to a NULL pointer dereference.

2) Integer underflow (CVE-ID: CVE-2020-24370)

The vulnerability allows a remote non-authenticated attacker to perform service disruption.

ldebug.c in Lua 5.4.0 allows a negation overflow and segmentation fault in getlocal and setlocal, as demonstrated by getlocal(3,2^31).

3) Input validation error (CVE-ID: CVE-2020-24371)

The vulnerability allows a remote non-authenticated attacker to perform service disruption.

lgc.c in Lua 5.4.0 mishandles the interaction between barriers and the sweep phase, leading to a memory access violation involving collectgarbage.

Remediation

Install update from vendor's website.

References

• https://github.com/lua/lua/commit/ae5b5ba529753c7a653901ffc29b5ea24c3fdf3a
• https://www.lua.org/bugs.html#5.4.0-12
• http://lua-users.org/lists/lua-l/2020-07/msg00324.html
• https://github.com/lua/lua/commit/a585eae6e7ada1ca9271607a4f48dfb17868ab7b
• https://github.com/lua/lua/commit/a6da1472c0c5e05ff249325f979531ad51533110
• https://www.lua.org/bugs.html#5.4.0-9