Out-of-bounds write in e2fsprogs (Alpine package)

1) Out-of-bounds write

EUVDB-ID: #VU24078

Risk: Low

CVSSv3.1: 7 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C]

CVE-ID: CVE-2019-5188

CWE-ID: CWE-787 - Out-of-bounds write

Exploit availability: No

Description

The vulnerability allows a local user to compromise vulnerable system.

The vulnerability exists due to a boundary error when processing untrusted input in the directory rehashing functionality in "rehash.c" within the "mutate_name()" function. A local user can use a specially crafted ext4 directory, trigger out-of-bounds write on the stack and execute arbitrary code on the target system.

Mitigation

Install update from vendor's website.

Vulnerable software versions

e2fsprogs (Alpine package): 1.43-r0 - 1.44.2-r1

External links

http://git.alpinelinux.org/aports/commit/?id=642db3215265db1cbf49b25d942ef9d11d3c410f
http://git.alpinelinux.org/aports/commit/?id=2ed804fc262d008a2558bd3ca7287479e85929ba
http://git.alpinelinux.org/aports/commit/?id=18b5cab25223debddf802a6309b15db6947dba96
http://git.alpinelinux.org/aports/commit/?id=948fd324de9029f91e5a736dd623b8f1390256e5
http://git.alpinelinux.org/aports/commit/?id=961349519affeaa193ce9d638736f4482ff4576a
http://git.alpinelinux.org/aports/commit/?id=00430c951fbd0bdf2423cd019cb974e2eb19361d

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.