#VU66491 Out-of-bounds write in Binutils - CVE-2021-20294

Vulnerability identifier: #VU66491

Vulnerability risk: Medium

CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P/U:Green]

CVE-ID: CVE-2021-20294

CWE-ID: CWE-787

Exploitation vector: Network

Exploit availability: Yes

Vulnerable software:
Binutils
Universal components / Libraries / Libraries used by multiple products

Vendor: GNU

Description

The vulnerability allows a remote attacker to compromise vulnerable system.

The vulnerability exists due to a boundary error when processing untrusted input in readelf. A remote attacker can create a specially crafted file, trick the victim into opening it using the affected software, trigger out-of-bounds write and execute arbitrary code on the target system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Binutils: 2.35 - 2.35.1

---

External links
https://bugzilla.redhat.com/show_bug.cgi?id=1943533
https://sourceware.org/bugzilla/show_bug.cgi?id=26929
https://lists.apache.org/thread.html/rf4c02775860db415b4955778a131c2795223f61cb8c6a450893651e4@%3Cissues.bookkeeper.apache.org%3E
https://lists.apache.org/thread.html/r58af02e294bd07f487e2c64ffc0a29b837db5600e33b6e698b9d696b@%3Cissues.bookkeeper.apache.org%3E
https://sourceware.org/git/?p=binutils-gdb.git;a=patch;h=372dd157272e0674d13372655cc60eaca9c06926

---

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

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.