CVE-2020-29573
Published: 6 December 2020
sysdeps/i386/ldbl2mpn.c in the GNU C Library (aka glibc or libc6) before 2.23 on x86 targets has a stack-based buffer overflow if the input to any of the printf family of functions is an 80-bit long double with a non-canonical bit pattern, as seen when passing a \x00\x04\x00\x00\x00\x00\x00\x00\x00\x04 value to sprintf. NOTE: the issue does not affect glibc by default in 2016 or later (i.e., 2.23 or later) because of commits made in 2015 for inlining of C99 math functions through use of GCC built-ins. In other words, the reference to 2.23 is intentional despite the mention of "Fixed for glibc 2.33" in the 26649 reference.
Notes
| Author | Note |
|---|---|
| mdeslaur | fixed in 2.23 and later |
Priority
Status
| Package | Release | Status |
|---|---|---|
|
eglibc Launchpad, Ubuntu, Debian |
bionic |
Does not exist
|
| focal |
Does not exist
|
|
| groovy |
Does not exist
|
|
| hirsute |
Does not exist
|
|
| impish |
Does not exist
|
|
| jammy |
Does not exist
|
|
| kinetic |
Does not exist
|
|
| lunar |
Does not exist
|
|
| mantic |
Does not exist
|
|
| trusty |
Needed
|
|
| upstream |
Needs triage
|
|
| xenial |
Does not exist
|
|
|
glibc Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(2.27-3ubuntu1.4)
|
| focal |
Not vulnerable
(2.31-0ubuntu9.1)
|
|
| groovy |
Not vulnerable
(2.32-0ubuntu3)
|
|
| hirsute |
Not vulnerable
(2.32-0ubuntu5)
|
|
| impish |
Not vulnerable
(2.32-0ubuntu5)
|
|
| jammy |
Not vulnerable
(2.32-0ubuntu5)
|
|
| kinetic |
Not vulnerable
(2.32-0ubuntu5)
|
|
| lunar |
Not vulnerable
(2.32-0ubuntu5)
|
|
| mantic |
Not vulnerable
(2.32-0ubuntu5)
|
|
| trusty |
Does not exist
|
|
| upstream |
Needs triage
|
|
| xenial |
Not vulnerable
(2.23-0ubuntu11.2)
|
|
|
Patches: upstream: https://sourceware.org/git/?p=glibc.git;h=d81f90ccd0109de9ed78aeeb8d86e2c6d4600690 upstream: https://sourceware.org/git/?p=glibc.git;h=8df4e219e43a4a257d0759b54fef8c488e2f282e |
||
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 7.5 |
| Attack vector | Network |
| Attack complexity | Low |
| Privileges required | None |
| User interaction | None |
| Scope | Unchanged |
| Confidentiality | None |
| Integrity impact | None |
| Availability impact | High |
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |