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TI-2026-47916 Aliases CVE-2026-68136GHSA-p4gp-483j-wr28

net: gro: fix double aggregation of flush-marked skbs

Priority MEDIUM 50CWE-476Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 11 fixed, 1 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-476.

Summary

In the Linux kernel, the following vulnerability has been resolved: net: gro: fix double aggregation of flush-marked skbs Commit 0ab03f353d36 ("net-gro: Fix GRO flush when receiving a GSO packet.") added a flush check to skb_gro_receive(), but skb_gro_receive_list() lacks the same validation. As a result, packets marked with NAPI_GRO_CB(skb)->flush may still be re-aggregated. This allows already-GRO'd packets with existing frag_list to be re-aggregated into a new GRO session, corrupting the frag_list chain structure. When skb_segment() attempts to unpack these malformed packets, it encounters invalid state and triggers a kernel panic. Scenario (Tethering/Device forwarding): 1. Driver: Generated aggregated packet P1 via LRO with frag_list 2. Dev A: Receives aggregated fraglist packet and flush flag set 3. Dev A: Re-enters GRO, skb_gro_receive_list() is called 4. Missing flush check allows re-aggregation despite flush flag 5. Frag_list chain becomes corrupted (loops or dangling refs) 6. Dev B: TX path calls skb_segment(), crashes on corrupted frag_list Root cause in skb_segment(): The check at line ~4891: if (hsize <= 0 && i >= nfrags && skb_headlen(list_skb) && (skb_headlen(list_skb) == len || sg)) { When frag_list is corrupted by double aggregation, when list_skb is a NULL pointer from skb->next, skb_headlen(list_skb) dereference NULL/corrupted pointers occurs. Call Trace: skb_headlen(NULL skb) skb_segment tcp_gso_segment tcp4_gso_segment inet_gso_segment skb_mac_gso_segment __skb_gso_segment skb_gso_segment validate_xmit_skb validate_xmit_skb_list sch_direct_xmit qdisc_restart __qdisc_run qdisc_run net_tx_action Fix: Add NAPI_GRO_CB(skb)->flush validation to the early-return check in skb_gro_receive_list(), matching the defensive programming pattern of skb_gro_receive().

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00539 45th percentileScored 2026-11-07
Fix Partial Linux (Linux): 5.10.266, 6.1.184, 6.6.153 +4Red Hat: 3 advisoriesRed Hat: 11 fixed, 1 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux5.6 and later5.10.266, 6.1.184, 6.6.153, 6.12.101, 6.18.42, 7.1.6, 7.2Patch availableCNA
  • Linux VendorLinux Affected 5.6 and later Fixed in 5.10.266, 6.1.184, 6.6.153, 6.12.101, 6.18.42, 7.1.6, 7.2 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*——Linux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions — — ·Linux

Remediation

  • Fix · CNA Linux (Linux) Fixed in 5.10.266, 6.1.184, 6.6.153, 6.12.101, 6.18.42, 7.1.6, 7.2

Red Hat 3 advisories

  • RHSA-2026:91565 Released 2026-10-28 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • 10Base-SMTV kernel-modules-internal-6.12.0-211.69.1.el10_2
    • Red Hat Enterprise Linux AppStream (v. 10) kernel-64k-debug-devel-6.12.0-211.69.1.el10_2, kernel-64k-debug-devel-matched-6.12.0-211.69.1.el10_2, kernel-64k-devel-6.12.0-211.69.1.el10_2 +12
    • Red Hat Enterprise Linux BaseOS (v. 10) kernel-6.12.0-211.69.1.el10_2, kernel-64k-6.12.0-211.69.1.el10_2, kernel-64k-core-6.12.0-211.69.1.el10_2 +29
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) kernel-tools-libs-devel-6.12.0-211.69.1.el10_2, libperf-6.12.0-211.69.1.el10_2
    • Red Hat Enterprise Linux Hidden (v. 10) kernel-modules-internal-6.12.0-211.69.1.el10_2
    • Red Hat Enterprise Linux Real Time (v. 10) kernel-rt-6.12.0-211.69.1.el10_2, kernel-rt-64k-6.12.0-211.69.1.el10_2, kernel-rt-64k-core-6.12.0-211.69.1.el10_2 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 10) kernel-rt-6.12.0-211.69.1.el10_2, kernel-rt-core-6.12.0-211.69.1.el10_2, kernel-rt-debug-6.12.0-211.69.1.el10_2 +9
  • RHSA-2026:89083 Released 2026-10-24 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • Red Hat Enterprise Linux BaseOS (v. 8) bpftool-4.18.0-553.178.1.el8_10, kernel-4.18.0-553.178.1.el8_10, kernel-abi-stablelists-4.18.0-553.178.1.el8_10 +19
    • Red Hat Enterprise Linux CRB (v. 8) kernel-tools-libs-devel-4.18.0-553.178.1.el8_10
  • RHSA-2026:89082 Released 2026-10-24 · Red Hat rating Important
    kernel-rt security, bug fix, and enhancement update
    • Red Hat Enterprise Linux NFV (v. 8) kernel-rt-4.18.0-553.178.1.rt7.519.el8_10, kernel-rt-core-4.18.0-553.178.1.rt7.519.el8_10, kernel-rt-debug-4.18.0-553.178.1.rt7.519.el8_10 +9
    • Red Hat Enterprise Linux RT (v. 8) kernel-rt-4.18.0-553.178.1.rt7.519.el8_10, kernel-rt-core-4.18.0-553.178.1.rt7.519.el8_10, kernel-rt-debug-4.18.0-553.178.1.rt7.519.el8_10 +7

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 9AffectedNo fix yet
10Base-SMTVFixed RHSA-2026:91565
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2026:91565
Red Hat Enterprise Linux BaseOS (v. 10)Fixed RHSA-2026:91565
Red Hat Enterprise Linux BaseOS (v. 8)Fixed RHSA-2026:89083
Red Hat Enterprise Linux CRB (v. 8)Fixed RHSA-2026:89083
Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)Fixed RHSA-2026:91565
Red Hat Enterprise Linux Hidden (v. 10)Fixed RHSA-2026:91565
Red Hat Enterprise Linux NFV (v. 8)Fixed RHSA-2026:89082
Red Hat Enterprise Linux RT (v. 8)Fixed RHSA-2026:89082
Red Hat Enterprise Linux Real Time (v. 10)Fixed RHSA-2026:91565
Red Hat Enterprise Linux Real Time for NFV (v. 10)Fixed RHSA-2026:91565
Not affected: 2 products
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-68136
  2. 2026-10-03 Alias added: GHSA-p4gp-483j-wr28
  3. 2026-10-16 CISA SSVC decision points changed
  4. 2026-10-20 Weakness changed · CISA ADP
  5. 2026-10-26 Fix available: RHSA-2026:89083 · Red Hat
  6. 2026-10-26 Fix available: Red Hat Enterprise Linux BaseOS (v. 8), Red Hat Enterprise Linux CRB (v. 8) · Red Hat
  7. 2026-10-26 Fix available: RHSA-2026:89082 · Red Hat
  8. 2026-10-26 Fix available: Red Hat Enterprise Linux NFV (v. 8), Red Hat Enterprise Linux RT (v. 8) · Red Hat
  9. 2026-10-29 Fix available: 10Base-SMTV, Red Hat Enterprise Linux AppStream (v. 10), Red Hat Enterprise Linux BaseOS (v. 10) +4 · Red Hat
  10. 2026-10-29 Fix available: RHSA-2026:91565 · Red Hat

References

Other 7

  • TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
  • TI-2021-02452 Incorrect authorization in Ubuntu linux kernel KEVCVSS 3.1HIGH 8.8
  • TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
  • TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
  • TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
See all 21741 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences