9.8

CVE-2026-64566: linux

CVSS: 9.8v3.1CriticalReceived
AliasesUBUNTU-CVE-2026-64566DEBIAN-CVE-2026-64566
Published 05-08-2026Last modified 17-08-2026
Open JSON

Vulnerability summary

CVE-2026-64566 is a critical (CVSS 9.8) vulnerability in linux. EPSS estimates a 0.35% chance of exploitation in the next 30 days, higher than 27.3% of scored vulnerabilities.

Overall risk
70/100
0100
High · default modelHow is this calculated?
CVSS score
9.8/10
010
Critical · v3.1 (CVE.org)
EPSS score
0.35%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 9 · Related 7
MGASA-2026-0336MGASA-2026-0337OPENSUSE-SU-2026:11476-1USN-8887-1USN-8887-2USN-8887-3

Timeline

  1. 05-08-2026
    PublishedVulnerability first disclosed.
  2. 17-08-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: xfrm: iptfs: propagate SKBFL_SHARED_FRAG in iptfs_skb_add_frags() When iptfs_skb_add_frags() copies frag references from the source frag walk into a new SKB, it increments the page reference count via __skb_frag_ref() but does not propagate SKBFL_SHARED_FRAG to the destination SKB's skb_shinfo->flags. If the source SKB carries shared frags (e.g. from a page-pool backed receive path), the new inner SKB will appear to ESP as having privately owned frags. A subsequent esp_input() call for a nested transport-mode SA then takes the no-COW fast path and decrypts in place, writing over pages that are still referenced by the outer IPTFS SKB. This causes kernel-visible memory corruption and can trigger a panic. All other frag-transfer helpers in the kernel (skb_try_coalesce, skb_gro_receive, __pskb_copy_fclone, skb_shift, skb_segment) correctly propagate SKBFL_SHARED_FRAG; align iptfs_skb_add_frags() with this convention by setting the flag inside the loop immediately after __skb_frag_ref() and nr_frags++, so every exit path that attaches a frag unconditionally propagates SKBFL_SHARED_FRAG.

CVSS metrics

4 scores · 4 sources · 1 version

EPSS trend

Probability

0.35%

Chance of exploitation in the next 30 days

Percentile

27%

Versus all other CVEs

30-day change

0.00 pp

From 0.35% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.35%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

No weakness data has been published for this record.

Affected systems

Ubuntu119 products
  • linux< 7.0.0-38.38
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-aws< 7.0.0-1014.14
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Debian1 product
  • linux< 7.1.6-1
Linux1 product
  • linux≥ 5f2b6a9095743a6bf1f34c43c4fe78fa8bdf5ad7, < d8aaf06b29f5a0b6186cf68d21c7d63678ee3891 | ≥ 5f2b6a9095743a6bf1f34c43c4fe78fa8bdf5ad7, < ffd64e0717efd83fbf3396ab4e5ac6d795dac4d0 | ≥ 5f2b6a9095743a6bf1f34c43c4fe78fa8bdf5ad7, < 430ea57d6daf765e88f90046afbfd1e071cb7200 | 6.14

3 vendors · 121 products

References

13 links
Show all 13 references