CVE-2026-80847

Source
https://cve.org/CVERecord?id=CVE-2026-80847
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-80847.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-80847
Downstream
Published
2026-09-04T15:54:57.441Z
Modified
2026-09-06T03:46:27.853568891Z
Summary
tcp: clamp route advmss to TCP_MIN_MSS
Details

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

tcp: clamp route advmss to TCPMINMSS

tcpselectinitial_window() assumes that callers never pass an MSS smaller than 1, but route-derived advmss values can violate that assumption.

A too-small explicit RTAXADVMSS is one way to get there, but it is not the only one. The same divide-by-zero can also be reached through the "default advmss" path when RTAXADVMSS is left at 0 and the effective advmss is later driven down by route MTU and minadvmss.

Introduce a tcpdstadvmss() helper that clamps route advmss to TCPMINMSS before TCP consumes it, and use it in the TCP paths that derive advmss from dst metrics. This keeps the effective MSS from dropping to zero before tcpselectinitial_window() rounds the receive window.

Database specific
{
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/80xxx/CVE-2026-80847.json",
    "cna_assigner": "Linux"
}
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
1da177e4c3f41524e886b7f1b8a0c1fc7321cac2
Fixed
6b8c20bf61924dfc38fefb145c9f7406d73fae53
Fixed
31cf2349361902769dc323e4dbf4b449795ec288
Fixed
870a9e42ecc6fe1b8c25d87af043cb0d9c178fe1

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
v3.1
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
v3.10
v3.10-rc1
v3.10-rc2
v3.10-rc3
v3.10-rc4
v3.10-rc5
v3.10-rc6
v3.10-rc7
v3.11
v3.11-rc1
v3.11-rc2
v3.11-rc3
v3.11-rc4
v3.11-rc5
v3.11-rc6
v3.11-rc7
v3.12
v3.12-rc1
v3.12-rc2
v3.12-rc3
v3.12-rc4
v3.12-rc5
v3.12-rc6
v3.12-rc7
v3.13
v3.13-rc1
v3.13-rc2
v3.13-rc3
v3.13-rc4
v3.13-rc5
v3.13-rc6
v3.13-rc7
v3.13-rc8
v3.14
v3.14-rc1
v3.14-rc2
v3.14-rc3
v3.14-rc4
v3.14-rc5
v3.14-rc6
v3.14-rc7
v3.14-rc8
v3.15
v3.15-rc1
v3.15-rc2
v3.15-rc3
v3.15-rc4
v3.15-rc5
v3.15-rc6
v3.15-rc7
v3.15-rc8
v3.16
v3.16-rc1
v3.16-rc2
v3.16-rc3
v3.16-rc4
v3.16-rc5
v3.16-rc6
v3.16-rc7
v3.17
v3.17-rc1
v3.17-rc2
v3.17-rc3
v3.17-rc4
v3.17-rc5
v3.17-rc6
v3.17-rc7
v3.18
v3.18-rc1
v3.18-rc2
v3.18-rc3
v3.18-rc4
v3.18-rc5
v3.18-rc6
v3.18-rc7
v3.19
v3.19-rc1
v3.19-rc2
v3.19-rc3
v3.19-rc4
v3.19-rc5
v3.19-rc6
v3.19-rc7
v3.2
v3.2-rc1
v3.2-rc2
v3.2-rc3
v3.2-rc4
v3.2-rc5
v3.2-rc6
v3.2-rc7
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
v3.5
v3.5-rc1
v3.5-rc2
v3.5-rc3
v3.5-rc4
v3.5-rc5
v3.5-rc6
v3.5-rc7
v3.6
v3.6-rc1
v3.6-rc2
v3.6-rc3
v3.6-rc4
v3.6-rc5
v3.6-rc6
v3.6-rc7
v3.7
v3.7-rc1
v3.7-rc2
v3.7-rc3
v3.7-rc4
v3.7-rc5
v3.7-rc6
v3.7-rc7
v3.7-rc8
v3.8
v3.8-rc1
v3.8-rc2
v3.8-rc3
v3.8-rc4
v3.8-rc5
v3.8-rc6
v3.8-rc7
v3.9
v3.9-rc1
v3.9-rc2
v3.9-rc3
v3.9-rc4
v3.9-rc5
v3.9-rc6
v3.9-rc7
v3.9-rc8
v4.*
v4.0
v4.0-rc1
v4.0-rc2
v4.0-rc3
v4.0-rc4
v4.0-rc5
v4.0-rc6
v4.0-rc7
v4.1
v4.1-rc1
v4.1-rc2
v4.1-rc3
v4.1-rc4
v4.1-rc5
v4.1-rc6
v4.1-rc7
v4.1-rc8
v4.10
v4.10-rc1
v4.10-rc2
v4.10-rc3
v4.10-rc4
v4.10-rc5
v4.10-rc6
v4.10-rc7
v4.10-rc8
v4.11
v4.11-rc1
v4.11-rc2
v4.11-rc3
v4.11-rc4
v4.11-rc5
v4.11-rc6
v4.11-rc7
v4.11-rc8
v4.12
v4.12-rc1
v4.12-rc2
v4.12-rc3
v4.12-rc4
v4.12-rc5
v4.12-rc6
v4.12-rc7
v4.13
v4.13-rc1
v4.13-rc2
v4.13-rc3
v4.13-rc4
v4.13-rc5
v4.13-rc6
v4.13-rc7
v4.14
v4.14-rc1
v4.14-rc2
v4.14-rc3
v4.14-rc4
v4.14-rc5
v4.14-rc6
v4.14-rc7
v4.14-rc8
v4.15
v4.15-rc1
v4.15-rc2
v4.15-rc3
v4.15-rc4
v4.15-rc5
v4.15-rc6
v4.15-rc7
v4.15-rc8
v4.15-rc9
v4.16
v4.16-rc1
v4.16-rc2
v4.16-rc3
v4.16-rc4
v4.16-rc5
v4.16-rc6
v4.16-rc7
v4.17
v4.17-rc1
v4.17-rc2
v4.17-rc3
v4.17-rc4
v4.17-rc5
v4.17-rc6
v4.17-rc7
v4.18
v4.18-rc1
v4.18-rc2
v4.18-rc3
v4.18-rc4
v4.18-rc5
v4.18-rc6
v4.18-rc7
v4.18-rc8
v4.19
v4.19-rc1
v4.19-rc2
v4.19-rc3
v4.19-rc4
v4.19-rc5
v4.19-rc6
v4.19-rc7
v4.19-rc8
v4.2
v4.2-rc1
v4.2-rc2
v4.2-rc3
v4.2-rc4
v4.2-rc5
v4.2-rc6
v4.2-rc7
v4.2-rc8
v4.20
v4.20-rc1
v4.20-rc2
v4.20-rc3
v4.20-rc4
v4.20-rc5
v4.20-rc6
v4.20-rc7
v4.3
v4.3-rc1
v4.3-rc2
v4.3-rc3
v4.3-rc4
v4.3-rc5
v4.3-rc6
v4.3-rc7
v4.4
v4.4-rc1
v4.4-rc2
v4.4-rc3
v4.4-rc4
v4.4-rc5
v4.4-rc6
v4.4-rc7
v4.4-rc8
v4.5
v4.5-rc1
v4.5-rc2
v4.5-rc3
v4.5-rc4
v4.5-rc5
v4.5-rc6
v4.5-rc7
v4.6
v4.6-rc1
v4.6-rc2
v4.6-rc3
v4.6-rc4
v4.6-rc5
v4.6-rc6
v4.6-rc7
v4.7
v4.7-rc1
v4.7-rc2
v4.7-rc3
v4.7-rc4
v4.7-rc5
v4.7-rc6
v4.7-rc7
v4.8
v4.8-rc1
v4.8-rc2
v4.8-rc3
v4.8-rc4
v4.8-rc5
v4.8-rc6
v4.8-rc7
v4.8-rc8
v4.9
v4.9-rc1
v4.9-rc2
v4.9-rc3
v4.9-rc4
v4.9-rc5
v4.9-rc6
v4.9-rc7
v4.9-rc8
v5.*
v5.0
v5.0-rc1
v5.0-rc2
v5.0-rc3
v5.0-rc4
v5.0-rc5
v5.0-rc6
v5.0-rc7
v5.0-rc8
v5.1
v5.1-rc1
v5.1-rc2
v5.1-rc3
v5.1-rc4
v5.1-rc5
v5.1-rc6
v5.1-rc7
v5.10
v5.10-rc1
v5.10-rc2
v5.10-rc3
v5.10-rc4
v5.10-rc5
v5.10-rc6
v5.10-rc7
v5.11
v5.11-rc1
v5.11-rc2
v5.11-rc3
v5.11-rc4
v5.11-rc5
v5.11-rc6
v5.11-rc7
v5.12
v5.12-rc1
v5.12-rc1-dontuse
v5.12-rc2
v5.12-rc3
v5.12-rc4
v5.12-rc5
v5.12-rc6
v5.12-rc7
v5.12-rc8
v5.13
v5.13-rc1
v5.13-rc2
v5.13-rc3
v5.13-rc4
v5.13-rc5
v5.13-rc6
v5.13-rc7
v5.14
v5.14-rc1
v5.14-rc2
v5.14-rc3
v5.14-rc4
v5.14-rc5
v5.14-rc6
v5.14-rc7
v5.15
v5.15-rc1
v5.15-rc2
v5.15-rc3
v5.15-rc4
v5.15-rc5
v5.15-rc6
v5.15-rc7
v5.16
v5.16-rc1
v5.16-rc2
v5.16-rc3
v5.16-rc4
v5.16-rc5
v5.16-rc6
v5.16-rc7
v5.16-rc8
v5.17
v5.17-rc1
v5.17-rc2
v5.17-rc3
v5.17-rc4
v5.17-rc5
v5.17-rc6
v5.17-rc7
v5.17-rc8
v5.18
v5.18-rc1
v5.18-rc2
v5.18-rc3
v5.18-rc4
v5.18-rc5
v5.18-rc6
v5.18-rc7
v5.19
v5.19-rc1
v5.19-rc2
v5.19-rc3
v5.19-rc4
v5.19-rc5
v5.19-rc6
v5.19-rc7
v5.19-rc8
v5.2
v5.2-rc1
v5.2-rc2
v5.2-rc3
v5.2-rc4
v5.2-rc5
v5.2-rc6
v5.2-rc7
v5.3
v5.3-rc1
v5.3-rc2
v5.3-rc3
v5.3-rc4
v5.3-rc5
v5.3-rc6
v5.3-rc7
v5.3-rc8
v5.4
v5.4-rc1
v5.4-rc2
v5.4-rc3
v5.4-rc4
v5.4-rc5
v5.4-rc6
v5.4-rc7
v5.4-rc8
v5.5
v5.5-rc1
v5.5-rc2
v5.5-rc3
v5.5-rc4
v5.5-rc5
v5.5-rc6
v5.5-rc7
v5.6
v5.6-rc1
v5.6-rc2
v5.6-rc3
v5.6-rc4
v5.6-rc5
v5.6-rc6
v5.6-rc7
v5.7
v5.7-rc1
v5.7-rc2
v5.7-rc3
v5.7-rc4
v5.7-rc5
v5.7-rc6
v5.7-rc7
v5.8
v5.8-rc1
v5.8-rc2
v5.8-rc3
v5.8-rc4
v5.8-rc5
v5.8-rc6
v5.8-rc7
v5.9
v5.9-rc1
v5.9-rc2
v5.9-rc3
v5.9-rc4
v5.9-rc5
v5.9-rc6
v5.9-rc7
v5.9-rc8
v6.*
v6.0
v6.0-rc1
v6.0-rc2
v6.0-rc3
v6.0-rc4
v6.0-rc5
v6.0-rc6
v6.0-rc7
v6.1
v6.1-rc1
v6.1-rc2
v6.1-rc3
v6.1-rc4
v6.1-rc5
v6.1-rc6
v6.1-rc7
v6.1-rc8
v6.10
v6.10-rc1
v6.10-rc2
v6.10-rc3
v6.10-rc4
v6.10-rc5
v6.10-rc6
v6.10-rc7
v6.11
v6.11-rc1
v6.11-rc2
v6.11-rc3
v6.11-rc4
v6.11-rc5
v6.11-rc6
v6.11-rc7
v6.12
v6.12-rc1
v6.12-rc2
v6.12-rc3
v6.12-rc4
v6.12-rc5
v6.12-rc6
v6.12-rc7
v6.13
v6.13-rc1
v6.13-rc2
v6.13-rc3
v6.13-rc4
v6.13-rc5
v6.13-rc6
v6.13-rc7
v6.14
v6.14-rc1
v6.14-rc2
v6.14-rc3
v6.14-rc4
v6.14-rc5
v6.14-rc6
v6.14-rc7
v6.15
v6.15-rc1
v6.15-rc2
v6.15-rc3
v6.15-rc4
v6.15-rc5
v6.15-rc6
v6.15-rc7
v6.16
v6.16-rc1
v6.16-rc2
v6.16-rc3
v6.16-rc4
v6.16-rc5
v6.16-rc6
v6.16-rc7
v6.17
v6.17-rc1
v6.17-rc2
v6.17-rc3
v6.17-rc4
v6.17-rc5
v6.17-rc6
v6.17-rc7
v6.18
v6.18-rc1
v6.18-rc2
v6.18-rc3
v6.18-rc4
v6.18-rc5
v6.18-rc6
v6.18-rc7
v6.19
v6.19-rc1
v6.19-rc2
v6.19-rc3
v6.19-rc4
v6.19-rc5
v6.19-rc6
v6.19-rc7
v6.19-rc8
v6.2
v6.2-rc1
v6.2-rc2
v6.2-rc3
v6.2-rc4
v6.2-rc5
v6.2-rc6
v6.2-rc7
v6.2-rc8
v6.3
v6.3-rc1
v6.3-rc2
v6.3-rc3
v6.3-rc4
v6.3-rc5
v6.3-rc6
v6.3-rc7
v6.4
v6.4-rc1
v6.4-rc2
v6.4-rc3
v6.4-rc4
v6.4-rc5
v6.4-rc6
v6.4-rc7
v6.5
v6.5-rc1
v6.5-rc2
v6.5-rc3
v6.5-rc4
v6.5-rc5
v6.5-rc6
v6.5-rc7
v6.6
v6.6-rc1
v6.6-rc2
v6.6-rc3
v6.6-rc4
v6.6-rc5
v6.6-rc6
v6.6-rc7
v6.7
v6.7-rc1
v6.7-rc2
v6.7-rc3
v6.7-rc4
v6.7-rc5
v6.7-rc6
v6.7-rc7
v6.7-rc8
v6.8
v6.8-rc1
v6.8-rc2
v6.8-rc3
v6.8-rc4
v6.8-rc5
v6.8-rc6
v6.8-rc7
v6.9
v6.9-rc1
v6.9-rc2
v6.9-rc3
v6.9-rc4
v6.9-rc5
v6.9-rc6
v6.9-rc7
v7.*
v7.0
v7.0-rc1
v7.0-rc2
v7.0-rc3
v7.0-rc4
v7.0-rc5
v7.0-rc6
v7.0-rc7
v7.1
v7.1-rc1
v7.1-rc2
v7.1-rc3
v7.1-rc4
v7.1-rc5
v7.1-rc6
v7.1-rc7
v7.1.1
v7.1.10
v7.1.11
v7.1.12
v7.1.2
v7.1.3
v7.1.4
v7.1.5
v7.1.6
v7.1.7
v7.1.8
v7.1.9
v7.2
v7.2-rc1
v7.2-rc2
v7.2-rc3
v7.2-rc4
v7.2-rc5
v7.2-rc6
v7.2-rc7
v7.2.1
v7.2.2

Database specific

source
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-80847.json"

Linux / Kernel

Package

Name
Kernel

Affected ranges

Type
ECOSYSTEM
Events
Introduced
2.6.12
Fixed
7.1.13
Type
ECOSYSTEM
Events
Introduced
7.2.0
Fixed
7.2.3

Database specific

source
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-80847.json"