VulnTideExploited vulnerabilities, by vendor. Data as of .
Not in CISA KEVPublished EPSS 94.2% probability of exploitation in 30 days
Linux

CVE-2026-43284: xfrm: esp: avoid in-place decrypt on shared skb frags

Is it exploited?

Not on CISA's list. CISA has not added it to the Known Exploited Vulnerabilities catalog as of . If CISA adds it, this page shows it as known exploited.

How likely is exploitation in the next 30 days?
94.2%

EPSS score, percentile 99.8 of all scored records. A probability estimated by FIRST, not a report of exploitation.

How severe?
8.8 High

CVSS v3.1 base score, given by the CNA

What should I do?

CISA has set no required action, because the vulnerability is not in KEV.

The CVE record links no vendor advisory, patch or mitigation.

Which versions are affected?

Affected

  • 4.11

Unaffected before 4.11; 5.10.255; 5.15.205; 5.15.206; 6.1.171; 6.1.172; and 5 more

Versions by product

Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of ; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of ; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of . About the data.

What to do

Advisories and patches

The CVE record links no vendor advisory, patch or mitigation.

Affected products and versions

As listed in the CVE record.

Linux Linux
StatusVersions
Affectedfrom cac2661c53f3 to before a6cb440f274a
Affectedfrom cac2661c53f3 to before ab8b995323e5
Affectedfrom cac2661c53f3 to before fe785bb3a809
Affectedfrom cac2661c53f3 to before 5d55c7336f80
Affectedfrom cac2661c53f3 to before 8253aab4659c
Affectedfrom cac2661c53f3 to before 50ed1e787310
Affectedfrom cac2661c53f3 to before b54edf1e9a3f
Affectedfrom cac2661c53f3 to before 71a1d9d985d2
Affectedfrom cac2661c53f3 to before 52646cbd00e7
Affectedfrom cac2661c53f3 to before f4c50a4034e6

Versions not listed are: unaffected.

Linux Linux
StatusVersions
Affected4.11
Unaffectedbefore 4.11
Unaffected5.10.255
Unaffected5.15.205
Unaffected5.15.206
Unaffected6.1.171
Unaffected6.1.172
Unaffected6.6.138
Unaffected6.12.87
Unaffected6.18.28
Unaffected7.0.5
Unaffected7.1

Versions not listed are: affected.

Versions the record lists as unaffected: 5.10.255, 5.15.205, 5.15.206, 6.1.171, 6.1.172, 6.6.138, 6.12.87, 6.18.28.

Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of . About the data.

About this vulnerability

In the Linux kernel, the following vulnerability has been resolved: xfrm: esp: avoid in-place decrypt on shared skb frags MSG_SPLICE_PAGES can attach pages from a pipe directly to an skb. TCP marks such skbs with SKBFL_SHARED_FRAG after skb_splice_from_iter(), so later paths that may modify packet data can first make a private copy. The IPv4/IPv6 datagram append paths did not set this flag when…

Summary: CVE record, as of .

  • CISA has not added CVE-2026-43284 to its Known Exploited Vulnerabilities (KEV) catalog, as of 28 Oct 2026.
  • The CVE record was published on 8 May 2026.
  • The CVE record carries a CVSS v3.1 base score of 8.8 (High), given by its CNA.
  • FIRST's EPSS model puts the probability of exploitation in the next 30 days at 94.2% (percentile 99.8), as of 28 Oct 2026. EPSS is a statistical estimate, not a report of exploitation.
  • CISA's SSVC assessment in the CVE record: exploitation poc, automatable no, technical impact total.

Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of ; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of ; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of . About the data.

Description

xfrm: esp: avoid in-place decrypt on shared skb frags

In the Linux kernel, the following vulnerability has been resolved: xfrm: esp: avoid in-place decrypt on shared skb frags MSG_SPLICE_PAGES can attach pages from a pipe directly to an skb. TCP marks such skbs with SKBFL_SHARED_FRAG after skb_splice_from_iter(), so later paths that may modify packet data can first make a private copy. The IPv4/IPv6 datagram append paths did not set this flag when splicing pages into UDP skbs. That leaves an ESP-in-UDP packet made from shared pipe pages looking like an ordinary uncloned nonlinear skb. ESP input then takes the no-COW fast path for uncloned skbs without a frag_list and decrypts in place over data that is not owned privately by the skb. Mark IPv4/IPv6 datagram splice frags with SKBFL_SHARED_FRAG, matching TCP. Also make ESP input fall back to skb_cow_data() when the flag is present, so ESP does not decrypt externally backed frags in place. Private nonlinear skb frags still use the existing fast path. This intentionally does not change ESP output. In esp_output_head(), the path that appends the ESP trailer to existing skb tailroom without calling skb_cow_data() is not reachable for nonlinear skbs: skb_tailroom() returns zero when skb->data_len is nonzero, while ESP tailen is positive. Thus ESP output will either use the separate destination-frag path or fall back to skb_cow_data().

Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of . About the data.

Weakness

  • CWE-123: Write-what-where Condition

CWE and CAPEC are maintained by MITRE; the entries are those named in the CVE record.

Timeline

DateEvent
CVE record published
CVE record last updated

References

Known exploited Linux vulnerabilities

  • CVE-2026-46300: Linux Kernel Missing Initialization of a Variable Vulnerability (added )
  • CVE-2025-39682: Linux Kernel Improper Check for Unusual or Exceptional Conditions Vulnerability (added )
  • CVE-2025-39964: Linux Kernel Race Condition Vulnerability (added )
  • CVE-2026-53266: Linux Kernel Out-of-Bounds Write Vulnerability (added )
  • CVE-2026-53362: Linux Kernel Unspecified Vulnerability (added )