CVE-2020-15945

2020-07-2400:00:00

ubuntu.com

lua 5.4.0

segmentation fault

changedline

ldebug.c

cve-2020-15945

flow of control

vulnerable code

CVSS2

2.1

Attack Vector

LOCAL

Attack Complexity

LOW

Authentication

NONE

Confidentiality Impact

NONE

Integrity Impact

NONE

Availability Impact

PARTIAL

AV:L/AC:L/Au:N/C:N/I:N/A:P

CVSS3

5.5

Attack Vector

LOCAL

Attack Complexity

LOW

Privileges Required

LOW

User Interaction

NONE

Scope

UNCHANGED

Confidentiality Impact

NONE

Integrity Impact

NONE

Availability Impact

HIGH

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

EPSS

Percentile

12.8%

JSON

Lua through 5.4.0 has 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.

Notes

Author	Note
sbeattie	older luas need checking as the code has changed but may still be vulnerable
mdeslaur	couldn’t reproduce on lua earlier than 5.4. No indication that earlier versions are vulnerable. Marking not-affected.