ipv6: mcast: add RCU protection to mld_newpack()
Priority MEDIUM 51Published · Updated
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Partial Red Hat: 3 without a fix
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat.
Summary
In the Linux kernel, the following vulnerability has been resolved: ipv6: mcast: add RCU protection to mld_newpack() mld_newpack() can be called without RTNL or RCU being held. Note that we no longer can use sock_alloc_send_skb() because ipv6.igmp_sk uses GFP_KERNEL allocations which can sleep. Instead use alloc_skb() and charge the net->ipv6.igmp_sk socket under RCU protection.
Why it matters now
EPSS 0.1693 97th percentileScored 2026-11-07
Fix Partial Linux (Linux): 5.15.179, 6.1.129, 6.6.79 +3Red Hat: 3 without a fix
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Linux | Linux | 2.6.26 and later | 5.15.179, 6.1.129, 6.6.79, 6.12.16, 6.13.4, 6.14 | Patch available | CNA |
- Linux VendorLinux Affected 2.6.26 and later Fixed in 5.15.179, 6.1.129, 6.6.79, 6.12.16, 6.13.4, 6.14 Patch available CNA
CPE configurations NVD · 3
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | 2.6.26 to before 5.15.179; 5.16 to before 6.1.129; 6.2 to before 6.6.79; 6.7 to before 6.12.16; 6.13 to before 6.13.4 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.14:rc1:*:*:*:*:*:* | 6.14 rc1 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.14:rc2:*:*:*:*:*:* | 6.14 rc2 | Vulnerable | Linux |
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 2.6.26 to before 5.15.179; 5.16 to before 6.1.129; 6.2 to before 6.6.79; 6.7 to before 6.12.16; 6.13 to before 6.13.4 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.14:rc1:*:*:*:*:*:* Versions 6.14 rc1 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.14:rc2:*:*:*:*:*:* Versions 6.14 rc2 Vulnerable ·Linux
Remediation
- Fix · CNA Linux (Linux) Fixed in 5.15.179, 6.1.129, 6.6.79, 6.12.16, 6.13.4, 6.14
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 10 | Affected | No fix planned: Will not fix |
| Red Hat Enterprise Linux 6 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 7 | Affected | No fix planned: Out of support scope |
Not affected: 2 products
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9
Timeline
- 2026-10-02 Threatist record created from CVE-2025-21758
- 2026-10-03 Alias added: GHSA-xv46-47mw-9vxc
References
Patch 6
- https://git.kernel.org/stable/c/29fa42197f26a97cde29fa8c40beddf44ea5c8f3
- https://git.kernel.org/stable/c/e8af3632a7f2da83e27b083f787bced1faba00b1
- https://git.kernel.org/stable/c/1b91c597b0214b1b462eb627ec02658c944623f2
- https://git.kernel.org/stable/c/25195f9d5ffcc8079ad743a50c0409dbdc48d98a
- https://git.kernel.org/stable/c/d60d493b0e65647e0335e6a7c4547abcea7df8e9
- https://git.kernel.org/stable/c/a527750d877fd334de87eef81f1cb5f0f0ca3373
More Linux Kernel vulnerabilities
- 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-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
- TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
Sources
- CVE-2025-21758 · CVE Program
- CVE-2025-21758 · NVD
- FIRST EPSS
- GHSA-xv46-47mw-9vxc · GitHub Advisory Database · CC BY 4.0
- CVE-2025-21758 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences