CVE-2020-24240
Publication date 25 August 2020
Last updated 24 July 2024
Ubuntu priority
Cvss 3 Severity Score
GNU Bison before 3.7.1 has a use-after-free in _obstack_free in lib/obstack.c (called from gram_lex) when a '\0' byte is encountered. NOTE: there is a risk only if Bison is used with untrusted input, and the observed bug happens to cause unsafe behavior with a specific compiler/architecture. The bug report was intended to show that a crash may occur in Bison itself, not that a crash may occur in code that is generated by Bison.
Status
Package | Ubuntu Release | Status |
---|---|---|
bison | 24.04 LTS noble |
Not affected
|
22.04 LTS jammy |
Vulnerable
|
|
20.04 LTS focal |
Vulnerable
|
|
18.04 LTS bionic |
Vulnerable
|
|
16.04 LTS xenial |
Vulnerable
|
|
14.04 LTS trusty | Not in release |
Severity score breakdown
Parameter | Value |
---|---|
Base score | 5.5 · Medium |
Attack vector | Local |
Attack complexity | Low |
Privileges required | None |
User interaction | Required |
Scope | Unchanged |
Confidentiality | None |
Integrity impact | None |
Availability impact | High |
Vector | CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H |