Vulnerability details
CVE-2026-46300
Actively exploited
Linux LinuxSiemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFPSiemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFPSiemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP
net: skbuff: preserve shared-frag marker during coalescing
CVSS 3.1
7.8High
Official description
In the Linux kernel, the following vulnerability has been resolved: net: skbuff: preserve shared-frag marker during coalescing skb_try_coalesce() can attach paged frags from @from to @to. If @from has SKBFL_SHARED_FRAG set, the resulting @to skb can contain the same externally-owned or page-cache-backed frags, but the shared-frag marker is currently lost. That breaks the invariant relied on by later in-place writers. In particular, ESP input checks skb_has_shared_frag() before deciding whether an uncloned nonlinear skb can skip skb_cow_data(). If TCP receive coalescing has moved shared frags into an unmarked skb, ESP can see skb_has_shared_frag() as false and decrypt in place over page-cache backed frags. Propagate SKBFL_SHARED_FRAG when skb_try_coalesce() transfers paged frags. The tailroom copy path does not need the marker because it copies bytes into @to's linear data rather than transferring frag descriptors.
Related news
CVSS scores
| Score | Version | Source | Vector |
|---|---|---|---|
| 7.8High | 3.1 | CVEProject cvelistV5 (CNA) (Linux) | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| 7.8High | 3.1 | CVEProject cvelistV5 (CNA) (redhat-SADP) | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
Affected products
| Vendor | Product | Versions | Source |
|---|---|---|---|
| Linux | Linux | 3.9 | CVEProject cvelistV5 (CNA) |
| Linux | Linux | cef401de7be8c4e155c6746bfccf721a4fa5fab9 ≤ v < 9d3e5fd19fe1063bf607219e8562fbd567b8e8d5 | CVEProject cvelistV5 (CNA) |
| Linux | Linux | cef401de7be8c4e155c6746bfccf721a4fa5fab9 ≤ v < 78bf6b6bb19541d19fbda6242e7cfe2c682763c0 | CVEProject cvelistV5 (CNA) |
| Linux | Linux | cef401de7be8c4e155c6746bfccf721a4fa5fab9 ≤ v < 760e1addc27ba1a7beb4a0a7e8b3e9ec49e7a34e | CVEProject cvelistV5 (CNA) |
| Linux | Linux | cef401de7be8c4e155c6746bfccf721a4fa5fab9 ≤ v < 3bd9e113d50034db99d7ef69fd8e5242d15e414a | CVEProject cvelistV5 (CNA) |
| Linux | Linux | cef401de7be8c4e155c6746bfccf721a4fa5fab9 ≤ v < 3884358a9286b17f389a72b1426fc4547c23c111 | CVEProject cvelistV5 (CNA) |
| Linux | Linux | cef401de7be8c4e155c6746bfccf721a4fa5fab9 ≤ v < f84eca5817390257cef78013d0112481c503b4a3 | CVEProject cvelistV5 (CNA) |
| Linux | Linux | cef401de7be8c4e155c6746bfccf721a4fa5fab9 ≤ v < 2f2b16022a2e10ca7bccfb98db5ed2ec0f72641c | CVEProject cvelistV5 (CNA) |
| Linux | Linux | cef401de7be8c4e155c6746bfccf721a4fa5fab9 ≤ v < 3599e6b3cc1ada96883d496a50a210d3afbb6987 | CVEProject cvelistV5 (CNA) |
| Siemens | SIMATIC S7-1500 CPU 1518-4 PN/DP MFP | V3.1.5 ≤ v | CVEProject cvelistV5 (CNA) |
| Siemens | SIMATIC S7-1500 CPU 1518-4 PN/DP MFP | V3.1.5 ≤ v | CVEProject cvelistV5 (CNA) |
| Siemens | SIMATIC S7-1500 CPU 1518-4 PN/DP MFP | V3.1.6 ≤ v < V3.1.7 | CVEProject cvelistV5 (CNA) |
| Siemens | SIMATIC S7-1500 CPU 1518-4 PN/DP MFP | V3.1.6 ≤ v < V3.1.7 | CVEProject cvelistV5 (CNA) |
| Siemens | SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP | V3.1.5 ≤ v | CVEProject cvelistV5 (CNA) |
| Siemens | SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP | V3.1.5 ≤ v | CVEProject cvelistV5 (CNA) |
| Siemens | SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP | V3.1.6 ≤ v < V3.1.7 | CVEProject cvelistV5 (CNA) |
| Siemens | SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP | V3.1.6 ≤ v < V3.1.7 | CVEProject cvelistV5 (CNA) |
| Siemens | SIPLUS S7-1500 CPU 1518-4 PN/DP MFP | V3.1.5 ≤ v | CVEProject cvelistV5 (CNA) |
| Siemens | SIPLUS S7-1500 CPU 1518-4 PN/DP MFP | V3.1.6 ≤ v < V3.1.7 | CVEProject cvelistV5 (CNA) |
References and advisories
51- https://git.kernel.org/stable/c/3599e6b3cc1ada96883d496a50a210d3afbb6987
- https://git.kernel.org/stable/c/2f2b16022a2e10ca7bccfb98db5ed2ec0f72641c
- https://git.kernel.org/stable/c/9d3e5fd19fe1063bf607219e8562fbd567b8e8d5
- https://git.kernel.org/stable/c/78bf6b6bb19541d19fbda6242e7cfe2c682763c0
- https://git.kernel.org/stable/c/760e1addc27ba1a7beb4a0a7e8b3e9ec49e7a34e
- https://git.kernel.org/stable/c/3bd9e113d50034db99d7ef69fd8e5242d15e414a
- https://git.kernel.org/stable/c/3884358a9286b17f389a72b1426fc4547c23c111
- https://git.kernel.org/stable/c/f84eca5817390257cef78013d0112481c503b4a3
- http://www.openwall.com/lists/oss-security/2026/05/13/5
- http://www.openwall.com/lists/oss-security/2026/05/21/11
- http://www.openwall.com/lists/oss-security/2026/05/21/12
- http://www.openwall.com/lists/oss-security/2026/05/21/13
- https://access.redhat.com/security/cve/CVE-2026-46300 vdb-entryx_refsource_REDHAT
- https://bugzilla.redhat.com/show_bug.cgi?id=2477015 issue-trackingx_refsource_REDHAT
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-46300.json x_sadp-csaf-vex
- https://access.redhat.com/errata/RHSA-2026:19540 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:33486 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHBA-2026:20032 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:21695 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:21690 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:28887 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:23233 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:20087 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:25044 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:34098 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:21656 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:23245 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:21702 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:23240 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:20299 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:19569 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:19705 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:20593 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:20054 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:20129 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:19568 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:19666 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:23470 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:20130 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:20051 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:19521 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:23471 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:23469 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:24814 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:23468 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:19664 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:19711 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:19875 vendor-advisoryx_refsource_REDHAT
- https://cert-portal.siemens.com/productcert/html/ssa-082556.html
- https://cert-portal.siemens.com/productcert/html/ssa-019113.html
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-46300 government-resource
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Details
- Published
- 2026-05-23
- Last updated
- 2026-10-29
- State
- Published
- Assigner (CNA)
- Linux
- Kolun priority
- 86 · Critical
CISA KEV catalog
- Date added
- 2026-10-28
- Due date
- 2026-10-31
- Used in ransomware
- Unknown
Exploit prediction (EPSS)
16.13%
Probability of exploitation in 30 days
96.9%
Percentile (among all CVEs)
SSVC assessment (CISA)
- Automatable
- No
- Exploitation
- Active
- Technical impact
- Total
Weaknesses (CWE)
- CWE-123Write-what-where Condition
- CWE-456Missing Initialization of a Variable