DEBIAN-CVE-2026-23003

In the Linux kernel, the following vulnerability has been resolved: ip6tunnel: use skbvlaninetprepare() in __ip6tnlrcv() Blamed commit did not take care of VLAN encapsulations as spotted by syzbot [1]. Use skbvlaninetprepare() instead of pskbinetmaypull(). [1] BUG: KMSAN: uninit-value in __INETECNdecapsulate include/net/inetecn.h:253 [inline] BUG: KMSAN: uninit-value in INETECNdecapsulate include/net/inetecn.h:275 [inline] BUG: KMSAN: uninit-value in IP6ECNdecapsulate+0x7a8/0x1fa0 include/net/inet_ecn.h:321 __INETECNdecapsulate include/net/inetecn.h:253 [inline] INETECNdecapsulate include/net/inetecn.h:275 [inline] IP6ECNdecapsulate+0x7a8/0x1fa0 include/net/inetecn.h:321 ip6ip6dscpecndecapsulate+0x16f/0x1b0 net/ipv6/ip6_tunnel.c:729 __ip6tnlrcv+0xed9/0x1b50 net/ipv6/ip6tunnel.c:860 ip6tnlrcv+0xc3/0x100 net/ipv6/ip6tunnel.c:903 grercv+0x1529/0x1b90 net/ipv6/ip6gre.c:-1 ip6protocoldeliverrcu+0x1c89/0x2c60 net/ipv6/ip6input.c:438 ip6inputfinish+0x1f4/0x4a0 net/ipv6/ip6input.c:489 NFHOOK include/linux/netfilter.h:318 [inline] ip6input+0x9c/0x330 net/ipv6/ip6input.c:500 ip6mcinput+0x7ca/0xc10 net/ipv6/ip6input.c:590 dstinput include/net/dst.h:474 [inline] ip6rcvfinish+0x958/0x990 net/ipv6/ip6input.c:79 NFHOOK include/linux/netfilter.h:318 [inline] ipv6rcv+0xf1/0x3c0 net/ipv6/ip6input.c:311 __netifreceiveskbonecore net/core/dev.c:6139 [inline] __netifreceiveskb+0x1df/0xac0 net/core/dev.c:6252 netifreceiveskbinternal net/core/dev.c:6338 [inline] netifreceiveskb+0x57/0x630 net/core/dev.c:6397 tunrxbatched+0x1df/0x980 drivers/net/tun.c:1485 tungetuser+0x5c0e/0x6c60 drivers/net/tun.c:1953 tunchrwriteiter+0x3e9/0x5c0 drivers/net/tun.c:1999 newsyncwrite fs/readwrite.c:593 [inline] vfswrite+0xbe2/0x15d0 fs/readwrite.c:686 ksyswrite fs/read_write.c:738 [inline] __dosyswrite fs/read_write.c:749 [inline] __sesyswrite fs/read_write.c:746 [inline] __x64syswrite+0x1fb/0x4d0 fs/readwrite.c:746 x64syscall+0x30ab/0x3e70 arch/x86/include/generated/asm/syscalls64.h:2 dosyscallx64 arch/x86/entry/syscall64.c:63 [inline] dosyscall64+0xd3/0xf80 arch/x86/entry/syscall64.c:94 entrySYSCALL64afterhwframe+0x77/0x7f Uninit was created at: slabpostallochook mm/slub.c:4960 [inline] slaballocnode mm/slub.c:5263 [inline] kmemcacheallocnodenoprof+0x9e7/0x17a0 mm/slub.c:5315 kmallocreserve+0x13c/0x4b0 net/core/skbuff.c:586 __allocskb+0x805/0x1040 net/core/skbuff.c:690 allocskb include/linux/skbuff.h:1383 [inline] allocskbwithfrags+0xc5/0xa60 net/core/skbuff.c:6712 sockallocsendpskb+0xacc/0xc60 net/core/sock.c:2995 tunallocskb drivers/net/tun.c:1461 [inline] tungetuser+0x1142/0x6c60 drivers/net/tun.c:1794 tunchrwriteiter+0x3e9/0x5c0 drivers/net/tun.c:1999 newsyncwrite fs/readwrite.c:593 [inline] vfswrite+0xbe2/0x15d0 fs/readwrite.c:686 ksyswrite fs/readwrite.c:738 [inline] __dosyswrite fs/read_write.c:749 [inline] __sesyswrite fs/read_write.c:746 [inline] __x64syswrite+0x1fb/0x4d0 fs/readwrite.c:746 x64syscall+0x30ab/0x3e70 arch/x86/include/generated/asm/syscalls64.h:2 dosyscallx64 arch/x86/entry/syscall64.c:63 [inline] dosyscall64+0xd3/0xf80 arch/x86/entry/syscall64.c:94 entrySYSCALL64afterhwframe+0x77/0x7f CPU: 0 UID: 0 PID: 6465 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(none) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025

References

https://security-tracker.debian.org/tracker/CVE-2026-23003

Affected packages

Debian:11 / linux

Package

Name: linux
Purl: pkg:deb/debian/linux?arch=source

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Fixed

5.10.249-1

Affected versions

5.*

5.10.46-4

5.10.46-5

5.10.70-1~bpo10+1

5.10.70-1

5.10.84-1

5.10.92-1~bpo10+1

5.10.92-1

5.10.92-2

5.10.103-1~bpo10+1

5.10.103-1

5.10.106-1

5.10.113-1

5.10.120-1~bpo10+1

5.10.120-1

5.10.127-1

5.10.127-2~bpo10+1

5.10.127-2

5.10.136-1

5.10.140-1

5.10.148-1

5.10.149-1

5.10.149-2

5.10.158-1

5.10.158-2

5.10.162-1

5.10.178-1

5.10.178-2

5.10.178-3

5.10.179-1

5.10.179-2

5.10.179-3

5.10.179-4

5.10.179-5

5.10.191-1

5.10.197-1

5.10.205-1

5.10.205-2

5.10.209-1

5.10.209-2

5.10.216-1

5.10.218-1

5.10.221-1

5.10.223-1

5.10.226-1

5.10.234-1

5.10.237-1

5.10.244-1

5.10.247-1

Ecosystem specific

{
    "urgency": "not yet assigned"
}

Database specific

source

"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-23003.json"

Debian:12 / linux

Package

Name: linux
Purl: pkg:deb/debian/linux?arch=source

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Fixed

6.1.162-1

Affected versions

6.*

6.1.27-1

6.1.37-1

6.1.38-1

6.1.38-2~bpo11+1

6.1.38-2

6.1.38-3

6.1.38-4~bpo11+1

6.1.38-4

6.1.52-1

6.1.55-1~bpo11+1

6.1.55-1

6.1.64-1

6.1.66-1

6.1.67-1

6.1.69-1~bpo11+1

6.1.69-1

6.1.76-1~bpo11+1

6.1.76-1

6.1.82-1

6.1.85-1

6.1.90-1~bpo11+1

6.1.90-1

6.1.94-1~bpo11+1

6.1.94-1

6.1.98-1

6.1.99-1

6.1.106-1

6.1.106-2

6.1.106-3

6.1.112-1

6.1.115-1

6.1.119-1

6.1.123-1

6.1.124-1

6.1.128-1

6.1.129-1

6.1.133-1

6.1.135-1

6.1.137-1

6.1.139-1

6.1.140-1

6.1.147-1

6.1.148-1

6.1.153-1

6.1.158-1

6.1.159-1

Ecosystem specific

{
    "urgency": "not yet assigned"
}

Database specific

source

"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-23003.json"

Debian:13 / linux

Package

Name: linux
Purl: pkg:deb/debian/linux?arch=source

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Fixed

6.12.69-1

Affected versions

6.*

6.12.38-1

6.12.41-1

6.12.43-1~bpo12+1

6.12.43-1

6.12.48-1

6.12.57-1~bpo12+1

6.12.57-1

6.12.63-1~bpo12+1

6.12.63-1

6.12.69-1~bpo12+1

Ecosystem specific

{
    "urgency": "not yet assigned"
}

Database specific

source

"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-23003.json"

Debian:14 / linux

Package

Name: linux
Purl: pkg:deb/debian/linux?arch=source

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Fixed

6.18.8-1

Affected versions

6.*

6.12.38-1

6.12.41-1

6.12.43-1~bpo12+1

6.12.43-1

6.12.48-1

6.12.57-1~bpo12+1

6.12.57-1

6.12.63-1~bpo12+1

6.12.63-1

6.12.69-1~bpo12+1

6.12.69-1

6.12.73-1~bpo12+1

6.12.73-1

6.12.74-1

6.12.74-2~bpo12+1

6.12.74-2

6.13~rc6-1~exp1

6.13~rc7-1~exp1

6.13.2-1~exp1

6.13.3-1~exp1

6.13.4-1~exp1

6.13.5-1~exp1

6.13.6-1~exp1

6.13.7-1~exp1

6.13.8-1~exp1

6.13.9-1~exp1

6.13.10-1~exp1

6.13.11-1~exp1

6.14.3-1~exp1

6.14.5-1~exp1

6.14.6-1~exp1

6.15~rc7-1~exp1

6.15-1~exp1

6.15.1-1~exp1

6.15.2-1~exp1

6.15.3-1~exp1

6.15.4-1~exp1

6.15.5-1~exp1

6.15.6-1~exp1

6.16~rc7-1~exp1

6.16-1~exp1

6.16.1-1~exp1

6.16.3-1~bpo13+1

6.16.3-1

6.16.5-1

6.16.6-1

6.16.7-1

6.16.8-1

6.16.9-1

6.16.10-1

6.16.11-1

6.16.12-1~bpo13+1

6.16.12-1

6.16.12-2

6.17.2-1~exp1

6.17.5-1~exp1

6.17.6-1

6.17.7-1

6.17.7-2

6.17.8-1~bpo13+1

6.17.8-1

6.17.9-1

6.17.10-1

6.17.11-1

6.17.12-1

6.17.13-1~bpo13+1

6.17.13-1

6.18~rc4-1~exp1

6.18~rc4-1~exp2

6.18~rc5-1~exp1

6.18~rc6-1~exp1

6.18~rc7-1~exp1

6.18.1-1~exp1

6.18.2-1~exp1

6.18.3-1

6.18.5-1~bpo13+1

6.18.5-1

Ecosystem specific

{
    "urgency": "not yet assigned"
}

Database specific

source

"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-23003.json"

Debian:11 / linux-6.1

Package

Name: linux-6.1
Purl: pkg:deb/debian/linux-6.1?arch=source

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Fixed

6.1.162-1~deb11u1

Affected versions

6.*

6.1.106-3~deb11u1

6.1.106-3~deb11u2

6.1.106-3~deb11u3

6.1.112-1~deb11u1

6.1.119-1~deb11u1

6.1.128-1~deb11u1

6.1.129-1~deb11u1

6.1.137-1~deb11u1

6.1.140-1~deb11u1

6.1.147-1~deb11u1

6.1.148-1~deb11u1

6.1.153-1~deb11u1

6.1.158-1~deb11u1

6.1.159-1~deb11u1

Ecosystem specific

{
    "urgency": "not yet assigned"
}

Database specific

source

"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-23003.json"