High severity · published Jun 25, 2026
CVE-2026-53268
netfilter: conntrack_irc: fix possible out-of-bounds read
8.2
CVSS
0.5%
EPSS
No
On KEV
Description
In the Linux kernel, the following vulnerability has been resolved:
netfilter: conntrack_irc: fix possible out-of-bounds read
When parsing fails after we've matched the command string we
should bail out instead of trying to match a different command.
This helper should be deprecated, given prevalence of TLS I doubt it has
any relevance in 2026.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 44% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
KE
Kernel · Linux
2.6.20 before 5.10.259; 5.11 before 5.15.210; 5.16 before 6.1.176; 6.2 before 6.6.143; 6.7 before 6.12.94; 6.13 before 6.18.36; +7 more · source: NVD
LI
Linux · Linux
869f37d8e48f3911eb70f38a994feaa8f8380008 before 4cdda7f868f48e2f81579371584fdbdce37df2c8; 869f37d8e48f3911eb70f38a994feaa8f8380008 before 8a1d6e40dedfe1068aee094d851bd69e289c9fd6; 869f37d8e48f3911eb70f38a994feaa8f8380008 before 0afc802160af0df61ed374fdb97fb34cfe5cdf2f; 869f37d8e48f3911eb70f38a994feaa8f8380008 before 7c34f91305292083253df6a9f6c8ede02d4ccaea; 869f37d8e48f3911eb70f38a994feaa8f8380008 before ddddd8271359961e403d11c90c9ba9fc38914f7e; 869f37d8e48f3911eb70f38a994feaa8f8380008 before 9e5da2379f968a3ea5a6e38921ab6201576466dc; +3 more · source: vendor
SS
SIMATIC S7-1500 CPU 1518-4 PN/DP MFP · Siemens
V3.1.6; V3.1.7; V3.1.6; V3.1.7 · source: CISA
SS
SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP · Siemens
V3.1.6; V3.1.7; V3.1.6; V3.1.7 · source: CISA
SS
SIMATIC S7-1500 TM MFP - GNU/Linux subsystem · Siemens
0 · source: CISA
SS
SIPLUS S7-1500 CPU 1518-4 PN/DP MFP · Siemens
V3.1.6; V3.1.7 · source: CISA
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-53268
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-53268
Patch
https://git.kernel.org/stable/c/0afc802160af0df61ed374fdb97fb34cfe5cdf2f
Patch
https://git.kernel.org/stable/c/4cdda7f868f48e2f81579371584fdbdce37df2c8
Patch
https://git.kernel.org/stable/c/573810f61bcd6b6815e2ff53bbdd2b9c9d747176
Patch
https://git.kernel.org/stable/c/66eba0ffce3b7e11449946b4cbbef8ea36112f56
Patch
https://git.kernel.org/stable/c/7c34f91305292083253df6a9f6c8ede02d4ccaea
Patch
https://git.kernel.org/stable/c/8a1d6e40dedfe1068aee094d851bd69e289c9fd6
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