CVE-2026-52943 (GCVE-0-2026-52943)
Vulnerability from cvelistv5 – Published: 2026-06-24 09:00 – Updated: 2026-09-08 08:49
VLAI
EPSS
VEX
Title
net: skbuff: fix missing zerocopy reference in pskb_carve helpers
Summary
In the Linux kernel, the following vulnerability has been resolved:
net: skbuff: fix missing zerocopy reference in pskb_carve helpers
pskb_carve_inside_header() and pskb_carve_inside_nonlinear() both copy
the old skb_shared_info header into a new buffer via memcpy(), which
includes the destructor_arg pointer (uarg) for MSG_ZEROCOPY skbs.
Neither function calls net_zcopy_get() for the new shinfo, creating an
unaccounted holder: every skb_shared_info with destructor_arg set will
call skb_zcopy_clear() once when freed, but the corresponding
net_zcopy_get() was never called for the new copy. Repeated calls
drive uarg->refcnt to zero prematurely, freeing ubuf_info_msgzc while
TX skbs still hold live destructor_arg pointers.
KASAN reports use-after-free on a freed ubuf_info_msgzc:
BUG: KASAN: slab-use-after-free in skb_release_data+0x77b/0x810
Read of size 8 at addr ffff88801574d3e8 by task poc/220
Call Trace:
skb_release_data+0x77b/0x810
kfree_skb_list_reason+0x13e/0x610
skb_release_data+0x4cd/0x810
sk_skb_reason_drop+0xf3/0x340
skb_queue_purge_reason+0x282/0x440
rds_tcp_inc_free+0x1e/0x30
rds_recvmsg+0x354/0x1780
__sys_recvmsg+0xdf/0x180
Allocated by task 219:
msg_zerocopy_realloc+0x157/0x7b0
tcp_sendmsg_locked+0x2892/0x3ba0
Freed by task 219:
ip_recv_error+0x74a/0xb10
tcp_recvmsg+0x475/0x530
The skb consuming the late access still referenced the same uarg via
shinfo->destructor_arg copied by pskb_carve_inside_nonlinear() without
a refcount bump. This has been verified to be reliably exploitable: a
working proof-of-concept achieves full root privilege escalation from
an unprivileged local user on a default kernel configuration.
The fix follows the pattern of pskb_expand_head() which has the same
memcpy/cloned structure. For pskb_carve_inside_header(), net_zcopy_get()
is placed after skb_orphan_frags() succeeds, so the orphan error path
needs no cleanup. For pskb_carve_inside_nonlinear(), net_zcopy_get() is
placed after all failure points and just before skb_release_data(), so
no error path needs cleanup at all -- matching pskb_expand_head() more
closely and avoiding the need for a balancing net_zcopy_put().
Severity
7.8 (High)
CWE
- CWE-911 - Improper Update of Reference Count
Assigner
References
12 references
Impacted products
10 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Linux | Linux |
Affected:
6fa01ccd883021105e9f8af7d04b9f156fa3494a , < 8dbed691e43a50903658130bde0fcb5abc425b37
(git)
Affected: 6fa01ccd883021105e9f8af7d04b9f156fa3494a , < 9b40bdc2a3298225dffab8158208a0d8c6300578 (git) Affected: 6fa01ccd883021105e9f8af7d04b9f156fa3494a , < fd470f0a97b8e9a125f520265d2f3b088ffb5b8a (git) Affected: 6fa01ccd883021105e9f8af7d04b9f156fa3494a , < ceafb893b12f23331dcc5ff9587e643c3a40ee9f (git) Affected: 6fa01ccd883021105e9f8af7d04b9f156fa3494a , < 2e0e74c59b2761a414d9f48d7bee1e45220b2427 (git) Affected: 6fa01ccd883021105e9f8af7d04b9f156fa3494a , < 96a4713ae041cc85e712bac682cd2e644004d6c6 (git) Affected: 6fa01ccd883021105e9f8af7d04b9f156fa3494a , < 474d6c771d798bca84f0a140b611e36743511e18 (git) Affected: 6fa01ccd883021105e9f8af7d04b9f156fa3494a , < 98d0912e9f841e5529a5b89a972805f34cb1c69d (git) |
guessed | |
| Linux | Linux |
Affected:
4.7
Unaffected: 0 , < 4.7 (semver) Unaffected: 5.10.259 , ≤ 5.10.* (semver) Unaffected: 5.15.210 , ≤ 5.15.* (semver) Unaffected: 6.1.176 , ≤ 6.1.* (semver) Unaffected: 6.6.143 , ≤ 6.6.* (semver) Unaffected: 6.12.93 , ≤ 6.12.* (semver) Unaffected: 6.18.35 , ≤ 6.18.* (semver) Unaffected: 7.0.12 , ≤ 7.0.* (semver) Unaffected: 7.1 , ≤ * (original_commit_for_fix) |
guessed | |
| Red Hat | Red Hat Enterprise Linux 10 |
cpe:/o:redhat:enterprise_linux:10
|
||
| Red Hat | Red Hat Enterprise Linux 6 |
cpe:/o:redhat:enterprise_linux:6
|
||
| Red Hat | Red Hat Enterprise Linux 7 |
cpe:/o:redhat:enterprise_linux:7
|
||
| Red Hat | Red Hat Enterprise Linux 8 |
cpe:/o:redhat:enterprise_linux:8
|
||
| Red Hat | Red Hat Enterprise Linux 9 |
cpe:/o:redhat:enterprise_linux:9
|
||
| Siemens | SIMATIC S7-1500 CPU 1518-4 PN/DP MFP |
Affected:
V3.1.6 , < *
(custom)
|
guessed | |
| Siemens | SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP |
Affected:
V3.1.6 , < *
(custom)
|
guessed | |
| Siemens | SIPLUS S7-1500 CPU 1518-4 PN/DP MFP |
Affected:
V3.1.6 , < *
(custom)
|
guessed |
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"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: skbuff: fix missing zerocopy reference in pskb_carve helpers\n\npskb_carve_inside_header() and pskb_carve_inside_nonlinear() both copy\nthe old skb_shared_info header into a new buffer via memcpy(), which\nincludes the destructor_arg pointer (uarg) for MSG_ZEROCOPY skbs.\nNeither function calls net_zcopy_get() for the new shinfo, creating an\nunaccounted holder: every skb_shared_info with destructor_arg set will\ncall skb_zcopy_clear() once when freed, but the corresponding\nnet_zcopy_get() was never called for the new copy. Repeated calls\ndrive uarg-\u003erefcnt to zero prematurely, freeing ubuf_info_msgzc while\nTX skbs still hold live destructor_arg pointers.\n\nKASAN reports use-after-free on a freed ubuf_info_msgzc:\n\n BUG: KASAN: slab-use-after-free in skb_release_data+0x77b/0x810\n Read of size 8 at addr ffff88801574d3e8 by task poc/220\n\n Call Trace:\n skb_release_data+0x77b/0x810\n kfree_skb_list_reason+0x13e/0x610\n skb_release_data+0x4cd/0x810\n sk_skb_reason_drop+0xf3/0x340\n skb_queue_purge_reason+0x282/0x440\n rds_tcp_inc_free+0x1e/0x30\n rds_recvmsg+0x354/0x1780\n __sys_recvmsg+0xdf/0x180\n\n Allocated by task 219:\n msg_zerocopy_realloc+0x157/0x7b0\n tcp_sendmsg_locked+0x2892/0x3ba0\n\n Freed by task 219:\n ip_recv_error+0x74a/0xb10\n tcp_recvmsg+0x475/0x530\n\nThe skb consuming the late access still referenced the same uarg via\nshinfo-\u003edestructor_arg copied by pskb_carve_inside_nonlinear() without\na refcount bump. This has been verified to be reliably exploitable: a\nworking proof-of-concept achieves full root privilege escalation from\nan unprivileged local user on a default kernel configuration.\n\nThe fix follows the pattern of pskb_expand_head() which has the same\nmemcpy/cloned structure. For pskb_carve_inside_header(), net_zcopy_get()\nis placed after skb_orphan_frags() succeeds, so the orphan error path\nneeds no cleanup. For pskb_carve_inside_nonlinear(), net_zcopy_get() is\nplaced after all failure points and just before skb_release_data(), so\nno error path needs cleanup at all -- matching pskb_expand_head() more\nclosely and avoiding the need for a balancing net_zcopy_put()."
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"url": "https://git.kernel.org/stable/c/96a4713ae041cc85e712bac682cd2e644004d6c6"
},
{
"url": "https://git.kernel.org/stable/c/474d6c771d798bca84f0a140b611e36743511e18"
},
{
"url": "https://git.kernel.org/stable/c/98d0912e9f841e5529a5b89a972805f34cb1c69d"
}
],
"title": "net: skbuff: fix missing zerocopy reference in pskb_carve helpers",
"x_generator": {
"engine": "bippy-1.2.0"
}
}
},
"cveMetadata": {
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"assignerShortName": "Linux",
"cveId": "CVE-2026-52943",
"datePublished": "2026-06-24T09:00:12.292Z",
"dateReserved": "2026-06-09T07:44:35.371Z",
"dateUpdated": "2026-09-08T08:49:45.607Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
"epss": {
"cve": "CVE-2026-52943",
"date": "2026-09-15",
"epss": "0.00238",
"percentile": "0.14975"
},
"microsoft_vex": {
"current_release_date": "2026-06-28T01:40:07.000Z",
"cve": "CVE-2026-52943",
"id": "msrc_CVE-2026-52943",
"initial_release_date": "2026-06-02T00:00:00.000Z",
"product_status:fixed": "1",
"product_status:known_affected": "1",
"source": "Microsoft CSAF VEX",
"status": "final",
"title": "net: skbuff: fix missing zerocopy reference in pskb_carve helpers",
"url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-52943.json",
"version": "2"
},
"nvd": "{\"cve\":{\"id\":\"CVE-2026-52943\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2026-06-24T10:17:19.293\",\"lastModified\":\"2026-09-08T09:18:11.903\",\"vulnStatus\":\"Modified\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nnet: skbuff: fix missing zerocopy reference in pskb_carve helpers\\n\\npskb_carve_inside_header() and pskb_carve_inside_nonlinear() both copy\\nthe old skb_shared_info header into a new buffer via memcpy(), which\\nincludes the destructor_arg pointer (uarg) for MSG_ZEROCOPY skbs.\\nNeither function calls net_zcopy_get() for the new shinfo, creating an\\nunaccounted holder: every skb_shared_info with destructor_arg set will\\ncall skb_zcopy_clear() once when freed, but the corresponding\\nnet_zcopy_get() was never called for the new copy. Repeated calls\\ndrive uarg-\u003erefcnt to zero prematurely, freeing ubuf_info_msgzc while\\nTX skbs still hold live destructor_arg pointers.\\n\\nKASAN reports use-after-free on a freed ubuf_info_msgzc:\\n\\n BUG: KASAN: slab-use-after-free in skb_release_data+0x77b/0x810\\n Read of size 8 at addr ffff88801574d3e8 by task poc/220\\n\\n Call Trace:\\n skb_release_data+0x77b/0x810\\n kfree_skb_list_reason+0x13e/0x610\\n skb_release_data+0x4cd/0x810\\n sk_skb_reason_drop+0xf3/0x340\\n skb_queue_purge_reason+0x282/0x440\\n rds_tcp_inc_free+0x1e/0x30\\n rds_recvmsg+0x354/0x1780\\n __sys_recvmsg+0xdf/0x180\\n\\n Allocated by task 219:\\n msg_zerocopy_realloc+0x157/0x7b0\\n tcp_sendmsg_locked+0x2892/0x3ba0\\n\\n Freed by task 219:\\n ip_recv_error+0x74a/0xb10\\n tcp_recvmsg+0x475/0x530\\n\\nThe skb consuming the late access still referenced the same uarg via\\nshinfo-\u003edestructor_arg copied by pskb_carve_inside_nonlinear() without\\na refcount bump. This has been verified to be reliably exploitable: a\\nworking proof-of-concept achieves full root privilege escalation from\\nan unprivileged local user on a default kernel configuration.\\n\\nThe fix follows the pattern of pskb_expand_head() which has the same\\nmemcpy/cloned structure. For pskb_carve_inside_header(), net_zcopy_get()\\nis placed after skb_orphan_frags() succeeds, so the orphan error path\\nneeds no cleanup. For pskb_carve_inside_nonlinear(), net_zcopy_get() is\\nplaced after all failure points and just before skb_release_data(), so\\nno error path needs cleanup at all -- matching pskb_expand_head() more\\nclosely and avoiding the need for a balancing net_zcopy_put().\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"net/core/skbuff.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"6fa01ccd883021105e9f8af7d04b9f156fa3494a\",\"lessThan\":\"8dbed691e43a50903658130bde0fcb5abc425b37\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"6fa01ccd883021105e9f8af7d04b9f156fa3494a\",\"lessThan\":\"9b40bdc2a3298225dffab8158208a0d8c6300578\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"6fa01ccd883021105e9f8af7d04b9f156fa3494a\",\"lessThan\":\"fd470f0a97b8e9a125f520265d2f3b088ffb5b8a\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"6fa01ccd883021105e9f8af7d04b9f156fa3494a\",\"lessThan\":\"ceafb893b12f23331dcc5ff9587e643c3a40ee9f\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"6fa01ccd883021105e9f8af7d04b9f156fa3494a\",\"lessThan\":\"2e0e74c59b2761a414d9f48d7bee1e45220b2427\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"6fa01ccd883021105e9f8af7d04b9f156fa3494a\",\"lessThan\":\"96a4713ae041cc85e712bac682cd2e644004d6c6\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"6fa01ccd883021105e9f8af7d04b9f156fa3494a\",\"lessThan\":\"474d6c771d798bca84f0a140b611e36743511e18\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"6fa01ccd883021105e9f8af7d04b9f156fa3494a\",\"lessThan\":\"98d0912e9f841e5529a5b89a972805f34cb1c69d\",\"versionType\":\"git\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"net/core/skbuff.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"4.7\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"4.7\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.10.259\",\"lessThanOrEqual\":\"5.10.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.15.210\",\"lessThanOrEqual\":\"5.15.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.1.176\",\"lessThanOrEqual\":\"6.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.6.143\",\"lessThanOrEqual\":\"6.6.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.12.93\",\"lessThanOrEqual\":\"6.12.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.18.35\",\"lessThanOrEqual\":\"6.18.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.0.12\",\"lessThanOrEqual\":\"7.0.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.1\",\"lessThanOrEqual\":\"*\",\"versionType\":\"original_commit_for_fix\",\"status\":\"unaffected\"}]}]},{\"source\":\"0b0ca135-0b70-47e7-9f44-1890c2a1c46c\",\"affectedData\":[{\"vendor\":\"Red 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MFP\",\"defaultStatus\":\"unknown\",\"versions\":[{\"version\":\"V3.1.6\",\"lessThan\":\"*\",\"versionType\":\"custom\",\"status\":\"affected\"}]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H\",\"baseScore\":7.8,\"baseSeverity\":\"HIGH\",\"attackVector\":\"LOCAL\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"LOW\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":1.8,\"impactScore\":5.9},{\"source\":\"0b0ca135-0b70-47e7-9f44-1890c2a1c46c\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H\",\"baseScore\":7.8,\"baseSeverity\":\"HIGH\",\"attackVector\":\"LOCAL\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"LOW\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":1.8,\"impactScore\":5.9}]},\"weaknesses\":[{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-416\"}]},{\"source\":\"0b0ca135-0b70-47e7-9f44-1890c2a1c46c\",\"type\":\"Secondary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-911\"}]}],\"configurations\":[{\"nodes\":[{\"operator\":\"OR\",\"negate\":false,\"cpeMatch\":[{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"4.7\",\"versionEndExcluding\":\"5.10.259\",\"matchCriteriaId\":\"3FA30F1C-F514-4A35-83AD-10A879443A42\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"5.11\",\"versionEndExcluding\":\"5.15.210\",\"matchCriteriaId\":\"5E938CDF-D1C4-43D0-98DC-9E11B6B55801\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"5.16\",\"versionEndExcluding\":\"6.1.176\",\"matchCriteriaId\":\"C4446623-5F2B-4DD8-8666-9FAAC285A757\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"6.2\",\"versionEndExcluding\":\"6.6.143\",\"matchCriteriaId\":\"9062F1CD-CAD6-4EA2-A73F-C06D4A887B8C\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"6.7\",\"versionEndExcluding\":\"6.12.93\",\"matchCriteriaId\":\"1E73413E-0629-41AA-A4D3-5A3D10A0BD63\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"6.13\",\"versionEndExcluding\":\"6.18.35\",\"matchCriteriaId\":\"0FCCB23A-7629-4386-93B6-B119237C4382\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"6.19\",\"versionEndExcluding\":\"7.0.12\",\"matchCriteriaId\":\"9161A938-0FA8-44BC-95FE-C5A271601AB3\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:*\",\"matchCriteriaId\":\"B1EF7059-E670-45F4-B422-54C40FA86390\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:*\",\"matchCriteriaId\":\"0D38F0BF-A728-4133-A358-D44A2F7EE6D6\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:*\",\"matchCriteriaId\":\"EC732D08-5F7B-46D9-B154-E60C7F4F0A97\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:*\",\"matchCriteriaId\":\"E5910A9D-F60A-409A-B486-FE66BFEBA9B9\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:7.1:rc5:*:*:*:*:*:*\",\"matchCriteriaId\":\"81DFF19E-9CF8-49C6-8C36-1E4038622933\"}]}]}],\"references\":[{\"url\":\"https://git.kernel.org/stable/c/2e0e74c59b2761a414d9f48d7bee1e45220b2427\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/474d6c771d798bca84f0a140b611e36743511e18\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/8dbed691e43a50903658130bde0fcb5abc425b37\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/96a4713ae041cc85e712bac682cd2e644004d6c6\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/98d0912e9f841e5529a5b89a972805f34cb1c69d\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/9b40bdc2a3298225dffab8158208a0d8c6300578\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/ceafb893b12f23331dcc5ff9587e643c3a40ee9f\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/fd470f0a97b8e9a125f5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Party Advisory\"]},{\"url\":\"https://bugzilla.redhat.com/show_bug.cgi?id=2492137\",\"source\":\"0b0ca135-0b70-47e7-9f44-1890c2a1c46c\",\"tags\":[\"Third Party Advisory\"]},{\"url\":\"https://cert-portal.siemens.com/productcert/html/ssa-019113.html\",\"source\":\"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e\"},{\"url\":\"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-52943.json\",\"source\":\"0b0ca135-0b70-47e7-9f44-1890c2a1c46c\",\"tags\":[\"Third Party Advisory\"]}]}}",
"redhat_vex": {
"aggregate_severity": "Important",
"current_release_date": "2026-07-06T20:55:55+00:00",
"cve": "CVE-2026-52943",
"id": "CVE-2026-52943",
"initial_release_date": "2026-06-24T00:00:00+00:00",
"product_status:known_not_affected": "274",
"source": "Red Hat CSAF VEX",
"status": "final",
"title": "kernel: net: skbuff: fix missing zerocopy reference in pskb_carve helpers",
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-52943.json",
"version": "3"
},
"suse_vex": {
"aggregate_severity": "important",
"current_release_date": "2026-09-10T17:00:25Z",
"cve": "CVE-2026-52943",
"id": "CVE-2026-52943",
"initial_release_date": "2026-06-25T02:19:38Z",
"product_status:first_fixed": "2",
"product_status:known_affected": "505",
"product_status:known_not_affected": "64",
"product_status:recommended": "650",
"source": "SUSE CSAF VEX",
"status": "interim",
"title": "SUSE CVE CVE-2026-52943",
"url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-52943.json",
"version": "28"
}
}
}
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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