Buffer overflow in Freebsd

CVE-2020-25577

In FreeBSD 12.2-STABLE before r368250, 11.4-STABLE before r368253, 12.2-RELEASE before p1, 12.1-RELEASE before p11 and 11.4-RELEASE before p5 rtsold(8) does not verify that the RDNSS option does not extend past the end of the received packet before processing its contents. While the kernel currently ignores such malformed packets, it passes them to userspace programs. Any programs expecting the kernel to do validation may be vulnerable to an overflow.

Vulnerability class: Buffer Overflow

EPSS: 0.015 (71.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

  • Freebsd — versions 11.4, 12.1, 12.2
  • N/a Freebsd — versions FreeBSD 12.2-RELEASE before p1, 12.1-RELEASE before p11, 11.4-RELEASE before p5

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2020-25577?
CVE-2020-25577 is a critical-severity vulnerability in Freebsd, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 9.8/10. Published 2021-03-29.
How severe is CVE-2020-25577?
Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2020-25577 known to be exploited?
2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.