CVE-2021-20314 Memory corruption in libspf2

Critical 9.8 Published 12 Aug 2021 Updated 13 Feb 2025

A stack buffer overflow in libspf2 allows attackers to cause denial of service or execute code via crafted SPF messages.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: Available

What is CVE-2021-20314?

CVE-2021-20314 is a critical memory corruption vulnerability in Fedoraproject Fedora, published on 12 Aug 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

Stack buffer overflow in libspf2 versions below 1.2.11 when processing certain SPF macros can lead to Denial of service and potentially code execution via malicious crafted SPF explanation messages.

Weakness: CWE-787

Which versions are affected by CVE-2021-20314?

It affects 3 products.

Linux distribution packages (6)

`libspf2` SUSE:Package Hub 15 SP1	All versions	`1.2.10-bp153.5.1`
`libspf2` SUSE:Package Hub 15 SP2	All versions	`1.2.10-bp153.5.1`
`libspf2` SUSE:Package Hub 15 SP3	All versions	`1.2.10-bp153.5.1`
`libspf2` openSUSE:Leap 15.2	All versions	`1.2.10-bp153.5.1`
`libspf2` openSUSE:Leap 15.3	All versions	`1.2.10-bp153.5.1`
`libspf2` openSUSE:Tumbleweed	All versions	`0.01-5.3`

Products include Fedoraproject Fedora, Libspf2 Libspf2, Redhat Enterprise Linux.

How do I fix CVE-2021-20314?

Upgrade to a fixed version.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2021-20314 being exploited?

There is no known exploitation of CVE-2021-20314 in the wild and no public exploit code.

All Fedoraproject Fedora vulnerabilities

Sources

Also known as ALPINE-CVE-2021-20314, DEBIAN-CVE-2021-20314, DLA-2739-1, DSA-4955-1, GHSA-7mf9-xf4j-h63m, MGASA-2021-0414 and 4 more.