High severity · published Oct 14, 2026
CVE-2026-101955
Junos OS: SRX Series: Malformed DNS packet causes service disruption when UTM Anti-Spam SBL is used
8.1
CVSS
0.5%
EPSS
No
On KEV
Description
A Stack-based Buffer Overflow vulnerability in the UTM Anti-Spam SBL of Juniper Networks Junos OS on SRX series allows an unauthenticated remote attacker to cause arbitrary code execution or a denial of service via a injected malformed DNS packet when Anti-Spam SBL inspection is enabled.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 45% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
JO
Junos OS · Juniper
before 23.2R2-S7.7; 23.4 before 23.4R2-S8.13; 24.2 before 24.2R2-S5.5; 24.4 before 24.4R2-S5; 25.2 before 25.2R2-S2; 25.4 before 25.4R1-S3; +1 more · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-101955
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-101955
vendor-advisory
https://supportportal.juniper.net/JSA112186
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