SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2020-5591

XACK DNS 1.11.0 to 1.11.4, 1.10.0 to 1.10.8, 1.8.0 to 1.8.23, 1.7.0 to 1.7.18, and versions before 1.7.0 allow remote attackers to cause a denial of service condition resulting in degradation of the recursive resolver's performance or compromising the…

HIGH 7.5EPSS 1.64%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (1.64%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

XACK DNS 1.11.0 to 1.11.4, 1.10.0 to 1.10.8, 1.8.0 to 1.8.23, 1.7.0 to 1.7.18, and versions before 1.7.0 allow remote attackers to cause a denial of service condition resulting in degradation of the recursive resolver's performance or compromising the recursive resolver as a reflector in a reflection attack.

CVSS 3.1
7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS
1.64% probability · 76th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-674
Affected
xack/xack dns
Source
vultures@jpcert.or.jp
EPSS trend
0%3%5%26 October 2026: 1.64%26 October 202626 October 2026

EPSS 1.6% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.