cbcvebase.
CVE-2026-23397
published 2026-03-26

CVE-2026-23397: In the Linux kernel, the following vulnerability has been resolved: nfnetlink_osf: validate individual option lengths in fingerprints nfnl_osf_add_callback()…

PriorityP430high7.1CVSS 3.1
AVLACLPRLUINSUCHINAH
EPSS
0.12%
2.4th percentile
In the Linux kernel, the following vulnerability has been resolved: nfnetlink_osf: validate individual option lengths in fingerprints nfnl_osf_add_callback() validates opt_num bounds and string NUL-termination but does not check individual option length fields. A zero-length option causes nf_osf_match_one() to enter the option matching loop even when foptsize sums to zero, which matches packets with no TCP options where ctx->optp is NULL: Oops: general protection fault KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] RIP: 0010:nf_osf_match_one (net/netfilter/nfnetlink_osf.c:98) Call Trace: nf_osf_match (net/netfilter/nfnetlink_osf.c:227) xt_osf_match_packet (net/netfilter/xt_osf.c:32) ipt_do_table (net/ipv4/netfilter/ip_tables.c:293) nf_hook_slow (net/netfilter/core.c:623) ip_local_deliver (net/ipv4/ip_input.c:262) ip_rcv (net/ipv4/ip_input.c:573) Additionally, an MSS option (kind=2) with length optsize == foptsize check. Reject fingerprints where any option has zero length, or where an MSS option has length less than 4, at add time rather than trusting these values in the packet matching hot path.

Affected

69 ranges· showing 25
VendorProductVersion rangeFixed in
debianlinux< linux 6.19.10-1 (forky)linux 6.19.10-1 (forky)
linuxlinux
linuxlinux>= 11eeef41d5f63c7d2f7fdfcc733eb7fb137cc384 < e9cf17b91e733fec725ebcc0b3098bc5ccd505e0e9cf17b91e733fec725ebcc0b3098bc5ccd505e0
linuxlinux>= 11eeef41d5f63c7d2f7fdfcc733eb7fb137cc384 < 3c11b5c2436a3a5b450612ab160e3a525b28cfb53c11b5c2436a3a5b450612ab160e3a525b28cfb5
linuxlinux>= 11eeef41d5f63c7d2f7fdfcc733eb7fb137cc384 < aa0574182c46963c3cdb8cde46ec93aca21100d8aa0574182c46963c3cdb8cde46ec93aca21100d8
linuxlinux>= 11eeef41d5f63c7d2f7fdfcc733eb7fb137cc384 < 224f4678812e1a7bc8341bcb666773a0aec5ea6f224f4678812e1a7bc8341bcb666773a0aec5ea6f
linuxlinux>= 11eeef41d5f63c7d2f7fdfcc733eb7fb137cc384 < ec8bf0571b142f29dc0b68ae2ac3952f7a464b38ec8bf0571b142f29dc0b68ae2ac3952f7a464b38
linuxlinux>= 11eeef41d5f63c7d2f7fdfcc733eb7fb137cc384 < 3932620c04c2938c93c0890c225960d3d34ba3553932620c04c2938c93c0890c225960d3d34ba355
linuxlinux>= 11eeef41d5f63c7d2f7fdfcc733eb7fb137cc384 < 4c6aa008b913e808c4f4d3cde36cb1d9bb5967c64c6aa008b913e808c4f4d3cde36cb1d9bb5967c6
linuxlinux>= 11eeef41d5f63c7d2f7fdfcc733eb7fb137cc384 < dbdfaae9609629a9569362e3b8f33d0a20fd783cdbdfaae9609629a9569362e3b8f33d0a20fd783c
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel>= 0 < 6.19.10-16.19.10-1
linuxlinux_kernel>= 2.6.31 < 6.1.1676.1.167
linuxlinux_kernel>= 2.6.31.1 < 5.10.2535.10.253
linuxlinux_kernel>= 5.11 < 5.15.2035.15.203
linuxlinux_kernel>= 5.16 < 6.1.1676.1.167
linuxlinux_kernel>= 6.13 < 6.18.206.18.20
linuxlinux_kernel>= 6.13.0 < 6.18.206.18.20

CVSS provenance

nvdv3.17.1HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
vendor_ubuntu7.1HIGH
vendor_msrc4.4MEDIUM
vendor_redhat4.4MEDIUM
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