CVE-2026-68118

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Source
https://cve.org/CVERecord?id=CVE-2026-68118
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-68118.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-68118
Downstream
Published
2026-08-10T11:58:38Z
Modified
2026-08-25T03:51:41Z
Severity
  • 8.2 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H CVSS Calculator
Summary
tcp: challenge ACK for non-exact RST in SYN-RECEIVED
Details

In the Linux kernel, the following vulnerability has been resolved:

tcp: challenge ACK for non-exact RST in SYN-RECEIVED

The SYN-RECEIVED request-socket path in tcp_check_req() accepts an in-window RST without requiring SEG.SEQ to exactly match RCV.NXT. A non-exact RST therefore removes the request instead of eliciting a challenge ACK.

RFC 9293 section 3.10.7.4 applies the RFC 5961 reset check in SYN-RECEIVED: an exact RST resets the connection, while a non-exact in-window RST must trigger a challenge ACK and be dropped.

Apply that check before the ACK-field validation, following the RFC sequence-number, RST, then ACK processing order. Factor the per-netns challenge ACK quota out of tcp_send_challenge_ack() so request sockets can share it. Use the request socket's send_ack() callback and its own out-of-window ACK timestamp to send and rate-limit the response.

Database specific 
{
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/68xxx/CVE-2026-68118.json"
}
References

Affected packages

Git / git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Affected ranges

Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
282f23c6ee343126156dd41218b22ece96d747e3
Fixed
8b0a3a094f4cae2fb92e4d08d4eef7246a9d9c49
Fixed
0fe4636665d14a258de70b4f3e8248e6d42038f1
Fixed
234f9ffbd9b2c1b24ec67200ea3cff07401bec48
Fixed
22cec809b048495310f206d9abbcdbbfbdce3ae3
Fixed
a28c4fcbf774e23b4779cae468e3497a5ad1f4a1
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Last Affected
86791bbfe5ed7b275be040cfeff049a1624af1b7
Last Affected
61f69dc4e40e41b0018f00fa4aeb23d3239556fb
Last Affected
34fb350281ced2a72707a5c0064f69992d440edb
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
3.0.58
Fixed
3.1
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
3.2.37
Fixed
3.3
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
3.4.25
Fixed
3.5

Affected versions

v2.*
v2.6.12-rc2
v2.6.12-rc3
v2.6.12-rc4
v2.6.13
v2.6.13-rc1
v2.6.13-rc2
v2.6.13-rc3
v2.6.13-rc4
v2.6.13-rc5
v2.6.13-rc6
v2.6.13-rc7
v2.6.14-rc1
v2.6.14-rc2
v2.6.14-rc3
v2.6.15-rc1
v2.6.15-rc2
v2.6.15-rc4
v2.6.15-rc5
v2.6.15-rc7
v2.6.16
v2.6.16-rc1
v2.6.16-rc2
v2.6.16-rc3
v2.6.16-rc4
v2.6.16-rc5
v2.6.16-rc6
v2.6.17
v2.6.17-rc1
v2.6.17-rc2
v2.6.17-rc3
v2.6.17-rc4
v2.6.17-rc5
v2.6.17-rc6
v2.6.18
v2.6.18-rc1
v2.6.18-rc2
v2.6.18-rc3
v2.6.18-rc5
v2.6.18-rc6
v2.6.19-rc1
v2.6.19-rc2
v2.6.20-rc1
v2.6.20-rc2
v2.6.20-rc3
v2.6.20-rc4
v2.6.20-rc5
v2.6.20-rc6
v2.6.20-rc7
v2.6.21
v2.6.21-rc1
v2.6.21-rc2
v2.6.21-rc3
v2.6.21-rc4
v2.6.21-rc5
v2.6.21-rc6
v2.6.21-rc7
v2.6.22
v2.6.22-rc1
v2.6.22-rc2
v2.6.22-rc3
v2.6.22-rc4
v2.6.22-rc5
v2.6.22-rc6
v2.6.22-rc7
v2.6.23
v2.6.23-rc1
v2.6.23-rc2
v2.6.23-rc3
v2.6.23-rc4
v2.6.23-rc5
v2.6.23-rc6
v2.6.23-rc7
v2.6.23-rc8
v2.6.23-rc9
v2.6.24
v2.6.24-rc1
v2.6.24-rc2
v2.6.24-rc3
v2.6.24-rc4
v2.6.24-rc5
v2.6.24-rc6
v2.6.24-rc7
v2.6.24-rc8
v2.6.25
v2.6.25-rc1
v2.6.25-rc2
v2.6.25-rc3
v2.6.25-rc4
v2.6.25-rc5
v2.6.25-rc6
v2.6.25-rc7
v2.6.25-rc8
v2.6.25-rc9
v2.6.26
v2.6.26-rc1
v2.6.26-rc2
v2.6.26-rc3
v2.6.26-rc4
v2.6.26-rc5
v2.6.26-rc6
v2.6.26-rc7
v2.6.26-rc8
v2.6.26-rc9
v2.6.27
v2.6.27-rc1
v2.6.27-rc2
v2.6.27-rc3
v2.6.27-rc4
v2.6.27-rc5
v2.6.27-rc6
v2.6.27-rc7
v2.6.27-rc8
v2.6.27-rc9
v2.6.28
v2.6.28-rc1
v2.6.28-rc2
v2.6.28-rc3
v2.6.28-rc4
v2.6.28-rc5
v2.6.28-rc6
v2.6.28-rc7
v2.6.28-rc8
v2.6.28-rc9
v2.6.29
v2.6.29-rc1
v2.6.29-rc2
v2.6.29-rc3
v2.6.29-rc4
v2.6.29-rc5
v2.6.29-rc6
v2.6.29-rc7
v2.6.29-rc8
v2.6.30
v2.6.30-rc1
v2.6.30-rc2
v2.6.30-rc3
v2.6.30-rc4
v2.6.30-rc5
v2.6.30-rc6
v2.6.30-rc7
v2.6.30-rc8
v2.6.31
v2.6.31-rc1
v2.6.31-rc2
v2.6.31-rc3
v2.6.31-rc4
v2.6.31-rc5
v2.6.31-rc6
v2.6.31-rc7
v2.6.31-rc8
v2.6.31-rc9
v2.6.32
v2.6.32-rc1
v2.6.32-rc2
v2.6.32-rc3
v2.6.32-rc4
v2.6.32-rc5
v2.6.32-rc6
v2.6.32-rc7
v2.6.32-rc8
v2.6.33
v2.6.33-rc1
v2.6.33-rc2
v2.6.33-rc3
v2.6.33-rc4
v2.6.33-rc5
v2.6.33-rc6
v2.6.33-rc7
v2.6.33-rc8
v2.6.34
v2.6.34-rc1
v2.6.34-rc2
v2.6.34-rc3
v2.6.34-rc4
v2.6.34-rc5
v2.6.34-rc6
v2.6.34-rc7
v2.6.35
v2.6.35-rc1
v2.6.35-rc2
v2.6.35-rc3
v2.6.35-rc4
v2.6.35-rc5
v2.6.35-rc6
v2.6.36
v2.6.36-rc1
v2.6.36-rc2
v2.6.36-rc3
v2.6.36-rc4
v2.6.36-rc5
v2.6.36-rc6
v2.6.36-rc7
v2.6.36-rc8
v2.6.37
v2.6.37-rc1
v2.6.37-rc2
v2.6.37-rc3
v2.6.37-rc4
v2.6.37-rc5
v2.6.37-rc6
v2.6.37-rc7
v2.6.37-rc8
v2.6.38
v2.6.38-rc1
v2.6.38-rc2
v2.6.38-rc3
v2.6.38-rc4
v2.6.38-rc5
v2.6.38-rc6
v2.6.38-rc7
v2.6.38-rc8
v2.6.39
v2.6.39-rc1
v2.6.39-rc2
v2.6.39-rc3
v2.6.39-rc4
v2.6.39-rc5
v2.6.39-rc6
v2.6.39-rc7
v3.*
v3.0
v3.0-rc1
v3.0-rc2
v3.0-rc3
v3.0-rc4
v3.0-rc5
v3.0-rc6
v3.0-rc7
v3.0.1
v3.0.10
v3.0.11
v3.0.12
v3.0.13
v3.0.14
v3.0.15
v3.0.16
v3.0.17
v3.0.18
v3.0.19
v3.0.2
v3.0.20
v3.0.21
v3.0.22
v3.0.23
v3.0.24
v3.0.25
v3.0.26
v3.0.27
v3.0.28
v3.0.29
v3.0.3
v3.0.30
v3.0.31
v3.0.32
v3.0.33
v3.0.34
v3.0.35
v3.0.36
v3.0.37
v3.0.38
v3.0.39
v3.0.4
v3.0.40
v3.0.41
v3.0.42
v3.0.43
v3.0.44
v3.0.45
v3.0.46
v3.0.47
v3.0.48
v3.0.49
v3.0.5
v3.0.50
v3.0.51
v3.0.52
v3.0.53
v3.0.54
v3.0.55
v3.0.56
v3.0.57
v3.0.6
v3.0.7
v3.0.8
v3.0.9
v3.1
v3.1-rc1
v3.1-rc10
v3.1-rc2
v3.1-rc3
v3.1-rc4
v3.1-rc5
v3.1-rc6
v3.1-rc7
v3.1-rc8
v3.1-rc9
v3.2
v3.2-rc1
v3.2-rc2
v3.2-rc3
v3.2-rc4
v3.2-rc5
v3.2-rc6
v3.2-rc7
v3.2.1
v3.2.10
v3.2.11
v3.2.12
v3.2.13
v3.2.14
v3.2.15
v3.2.16
v3.2.17
v3.2.18
v3.2.19
v3.2.2
v3.2.20
v3.2.21
v3.2.22
v3.2.23
v3.2.24
v3.2.25
v3.2.26
v3.2.27
v3.2.28
v3.2.29
v3.2.3
v3.2.30
v3.2.31
v3.2.32
v3.2.33
v3.2.34
v3.2.35
v3.2.36
v3.2.4
v3.2.5
v3.2.6
v3.2.7
v3.2.8
v3.2.9
v3.3
v3.3-rc1
v3.3-rc2
v3.3-rc3
v3.3-rc4
v3.3-rc5
v3.3-rc6
v3.3-rc7
v3.4
v3.4-rc1
v3.4-rc2
v3.4-rc3
v3.4-rc4
v3.4-rc5
v3.4-rc6
v3.4-rc7
v3.4.1
v3.4.10
v3.4.11
v3.4.12
v3.4.13
v3.4.14
v3.4.15
v3.4.16
v3.4.17
v3.4.18
v3.4.19
v3.4.2
v3.4.20
v3.4.21
v3.4.22
v3.4.23
v3.4.24
v3.4.3
v3.4.4
v3.4.5
v3.4.6
v3.4.7
v3.4.8
v3.4.9

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-68118.json"

Linux / Kernel

Package

Name
Kernel

Affected ranges

Type
ECOSYSTEM
Events
Introduced
3.6.0
Fixed
6.6.153
Type
ECOSYSTEM
Events
Introduced
6.7.0
Fixed
6.12.105
Type
ECOSYSTEM
Events
Introduced
6.13.0
Fixed
6.18.42
Type
ECOSYSTEM
Events
Introduced
6.19.0
Fixed
7.1.6

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-68118.json"