CVE-2020-25577
In FreeBSD 12.2-STABLE before r368250, 11.4-STABLE before r368253, 12.2-RELEASE before p1, 12.1...
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
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.
- Record
CVE-2020-25577- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - CVSS 2.0
- 10.0 High
AV:N/AC:L/Au:N/C:C/I:C/A:C - Weakness
- CWE-120
- Updated
- 2026-11-02
CVE List No score
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.
- Record
CVE-2020-25577- Updated
- 2026-11-02
EUVDEUVD-2020-18257 No score
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.
- Record
EUVD-2020-18257- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-r8gv-c2f3-665p No score
In FreeBSD 12.2-STABLE before r368250, 11.4-STABLE before r368253, 12.2-RELEASE before p1, 12.1...
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.
- Record
GHSA-r8gv-c2f3-665p- Weakness
- CWE-120
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2020-25577 is a critical vulnerability (CVSS 9.8) in Freebsd, published March 29, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.50%, the 74th percentile. No source names a fixed version.