CVE-2023-53333
published 2025-09-16CVE-2023-53333: In the Linux kernel, the following vulnerability has been resolved: netfilter: conntrack: dccp: copy entire header to stack buffer, not just basic one Eric…
PriorityP432high7.1CVSS 3.1
AVLACLPRLUINSUCHINAH
EPSS
0.14%
3.7th percentile
In the Linux kernel, the following vulnerability has been resolved:
netfilter: conntrack: dccp: copy entire header to stack buffer, not just basic one
Eric Dumazet says:
nf_conntrack_dccp_packet() has an unique:
dh = skb_header_pointer(skb, dataoff, sizeof(_dh), &_dh);
And nothing more is 'pulled' from the packet, depending on the content.
dh->dccph_doff, and/or dh->dccph_x ...)
So dccp_ack_seq() is happily reading stuff past the _dh buffer.
BUG: KASAN: stack-out-of-bounds in nf_conntrack_dccp_packet+0x1134/0x11c0
Read of size 4 at addr ffff000128f66e0c by task syz-executor.2/29371
[..]
Fix this by increasing the stack buffer to also include room for
the extra sequence numbers and all the known dccp packet type headers,
then pull again after the initial validation of the basic header.
While at it, mark packets invalid that lack 48bit sequence bit but
where RFC says the type MUST use them.
Compile tested only.
v2: first skb_header_pointer() now needs to adjust the size to
only pull the generic header. (Eric)
Heads-up: I intend to remove dccp conntrack support later this year.
Affected
19 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 6.1.52-1 (bookworm) | linux 6.1.52-1 (bookworm) |
| linux | linux | — | — |
| linux | linux | >= 2bc780499aa33311ec0f3e42624dfaa7be0ade5e < 337fdce450637ea663bc816edc2ba81e5cdad02e | 337fdce450637ea663bc816edc2ba81e5cdad02e |
| linux | linux | >= 2bc780499aa33311ec0f3e42624dfaa7be0ade5e < 9bdcda7abaf22f6453e5b5efb7eb4e524095d5d8 | 9bdcda7abaf22f6453e5b5efb7eb4e524095d5d8 |
| linux | linux | >= 2bc780499aa33311ec0f3e42624dfaa7be0ade5e < c052797ac36813419ad3bfa54cb8615db4b41f15 | c052797ac36813419ad3bfa54cb8615db4b41f15 |
| linux | linux | >= 2bc780499aa33311ec0f3e42624dfaa7be0ade5e < 5c618daa5038712c4a4ef8923905a2ea1b8836a1 | 5c618daa5038712c4a4ef8923905a2ea1b8836a1 |
| linux | linux | >= 2bc780499aa33311ec0f3e42624dfaa7be0ade5e < 26bd1f210d3783a691052c51d76bb8a8bbd24c67 | 26bd1f210d3783a691052c51d76bb8a8bbd24c67 |
| linux | linux | >= 2bc780499aa33311ec0f3e42624dfaa7be0ade5e < 8c0980493beed3a80d6329c44ab293dc8c032927 | 8c0980493beed3a80d6329c44ab293dc8c032927 |
| linux | linux | >= 2bc780499aa33311ec0f3e42624dfaa7be0ade5e < ff0a3a7d52ff7282dbd183e7fc29a1fe386b0c30 | ff0a3a7d52ff7282dbd183e7fc29a1fe386b0c30 |
| linux | linux_kernel | >= 0 < 5.10.191-1 | 5.10.191-1 |
| linux | linux_kernel | >= 0 < 6.1.52-1 | 6.1.52-1 |
| linux | linux_kernel | >= 0 < 6.4.4-1 | 6.4.4-1 |
| linux | linux_kernel | >= 0 < 6.4.4-1 | 6.4.4-1 |
| linux | linux_kernel | >= 2.6.26 < 5.4.251 | 5.4.251 |
| linux | linux_kernel | >= 5.11 < 5.15.121 | 5.15.121 |
| linux | linux_kernel | >= 5.16 < 6.1.39 | 6.1.39 |
| linux | linux_kernel | >= 5.5 < 5.10.188 | 5.10.188 |
| linux | linux_kernel | >= 6.2 < 6.3.13 | 6.3.13 |
| linux | linux_kernel | >= 6.4 < 6.4.4 | 6.4.4 |
CVSS provenance
nvdv3.17.1HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
osv7.1HIGH
vendor_debian7.1HIGH
vendor_redhat7.1HIGH
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Red Hat
kernel: netfilter: conntrack: dccp: copy entire header to stack buffer, not just basic one
vendor_redhat·2025-09-16·CVSS 7.1
CVE-2023-53333 [HIGH] CWE-125 kernel: netfilter: conntrack: dccp: copy entire header to stack buffer, not just basic one
kernel: netfilter: conntrack: dccp: copy entire header to stack buffer, not just basic one
In the Linux kernel, the following vulnerability has been resolved:
netfilter: conntrack: dccp: copy entire header to stack buffer, not just basic one
Eric Dumazet says:
nf_conntrack_dccp_packet() has an unique:
dh = skb_header_pointer(skb, dataoff, sizeof(_dh), &_dh);
And nothing more is 'pulled' from the packet, depending on the content.
dh->dccph_doff, and/or dh->dccph_x ...)
So dccp_ack_seq() is happily reading stuff past the _dh buffer.
BUG: KASAN: stack-out-of-bounds in nf_conntrack_dccp_packet+0x1134/0x11c0
Read of size 4 at addr ffff000128f66e0c by task syz-executor.2/29371
[..]
Fix this by increasing the stack buffer to also include room for
the extra sequence numbers and all the known dccp
Debian
CVE-2023-53333: linux - In the Linux kernel, the following vulnerability has been resolved: netfilter: ...
vendor_debian·2023·CVSS 7.1
CVE-2023-53333 [HIGH] CVE-2023-53333: linux - In the Linux kernel, the following vulnerability has been resolved: netfilter: ...
In the Linux kernel, the following vulnerability has been resolved: netfilter: conntrack: dccp: copy entire header to stack buffer, not just basic one Eric Dumazet says: nf_conntrack_dccp_packet() has an unique: dh = skb_header_pointer(skb, dataoff, sizeof(_dh), &_dh); And nothing more is 'pulled' from the packet, depending on the content. dh->dccph_doff, and/or dh->dccph_x ...) So dccp_ack_seq() is happily reading stuff past the _dh buffer. BUG: KASAN: stack-out-of-bounds in nf_conntrack_dccp_packet+0x1134/0x11c0 Read of size 4 at addr ffff000128f66e0c by task syz-executor.2/29371 [..] Fix this by increasing the stack buffer to also include room for the extra sequence numbers and all the known dccp packet type headers, then pull again after the initial validation of the basic header. Whil
OSV
CVE-2023-53333: In the Linux kernel, the following vulnerability has been resolved: netfilter: conntrack: dccp: copy entire header to stack buffer, not just basic one
osv·2025-09-16·CVSS 7.1
CVE-2023-53333 [HIGH] CVE-2023-53333: In the Linux kernel, the following vulnerability has been resolved: netfilter: conntrack: dccp: copy entire header to stack buffer, not just basic one
In the Linux kernel, the following vulnerability has been resolved: netfilter: conntrack: dccp: copy entire header to stack buffer, not just basic one Eric Dumazet says: nf_conntrack_dccp_packet() has an unique: dh = skb_header_pointer(skb, dataoff, sizeof(_dh), &_dh); And nothing more is 'pulled' from the packet, depending on the content. dh->dccph_doff, and/or dh->dccph_x ...) So dccp_ack_seq() is happily reading stuff past the _dh buffer. BUG: KASAN: stack-out-of-bounds in nf_conntrack_dccp_packet+0x1134/0x11c0 Read of size 4 at addr ffff000128f66e0c by task syz-executor.2/29371 [..] Fix this by increasing the stack buffer to also include room for the extra sequence numbers and all the known dccp packet type headers, then pull again after the initial validation of the basic header. Whil
GHSA
GHSA-r2m9-j67m-7grm: In the Linux kernel, the following vulnerability has been resolved:
netfilter: conntrack: dccp: copy entire header to stack buffer, not just basic on
ghsa_unreviewed·2025-09-16
CVE-2023-53333 [HIGH] CWE-125 GHSA-r2m9-j67m-7grm: In the Linux kernel, the following vulnerability has been resolved:
netfilter: conntrack: dccp: copy entire header to stack buffer, not just basic on
In the Linux kernel, the following vulnerability has been resolved:
netfilter: conntrack: dccp: copy entire header to stack buffer, not just basic one
Eric Dumazet says:
nf_conntrack_dccp_packet() has an unique:
dh = skb_header_pointer(skb, dataoff, sizeof(_dh), &_dh);
And nothing more is 'pulled' from the packet, depending on the content.
dh->dccph_doff, and/or dh->dccph_x ...)
So dccp_ack_seq() is happily reading stuff past the _dh buffer.
BUG: KASAN: stack-out-of-bounds in nf_conntrack_dccp_packet+0x1134/0x11c0
Read of size 4 at addr ffff000128f66e0c by task syz-executor.2/29371
[..]
Fix this by increasing the stack buffer to also include room for
the extra sequence numbers and all the known dccp packet type headers,
then pull again after the initial validation of the basic header
No detection rules found.
No public exploits indexed.
https://git.kernel.org/stable/c/26bd1f210d3783a691052c51d76bb8a8bbd24c67https://git.kernel.org/stable/c/337fdce450637ea663bc816edc2ba81e5cdad02ehttps://git.kernel.org/stable/c/5c618daa5038712c4a4ef8923905a2ea1b8836a1https://git.kernel.org/stable/c/8c0980493beed3a80d6329c44ab293dc8c032927https://git.kernel.org/stable/c/9bdcda7abaf22f6453e5b5efb7eb4e524095d5d8https://git.kernel.org/stable/c/c052797ac36813419ad3bfa54cb8615db4b41f15https://git.kernel.org/stable/c/ff0a3a7d52ff7282dbd183e7fc29a1fe386b0c30
2025-09-16
Published