Read the docs
TI-2025-25903 Aliases CVE-2025-38566GHSA-64hp-5254-q6pc

sunrpc: fix handling of server side tls alerts

Priority MEDIUM 50CWE-754Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 15 fixed, 2 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: sunrpc: fix handling of server side tls alerts Scott Mayhew discovered a security exploit in NFS over TLS in tls_alert_recv() due to its assumption it can read data from the msg iterator's kvec.. kTLS implementation splits TLS non-data record payload between the control message buffer (which includes the type such as TLS aler or TLS cipher change) and the rest of the payload (say TLS alert's level/description) which goes into the msg payload buffer. This patch proposes to rework how control messages are setup and used by sock_recvmsg(). If no control message structure is setup, kTLS layer will read and process TLS data record types. As soon as it encounters a TLS control message, it would return an error. At that point, NFS can setup a kvec backed msg buffer and read in the control message such as a TLS alert. Msg iterator can advance the kvec pointer as a part of the copy process thus we need to revert the iterator before calling into the tls_alert_recv.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00633 50th percentileScored 2026-11-07
Fix Partial Linux (Linux): 6.6.102, 6.12.42, 6.15.10 +2Red Hat: 4 advisoriesRed Hat: 15 fixed, 2 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
LinuxLinux6.4 and later6.6.102, 6.12.42, 6.15.10, 6.16.1, 6.17Patch availableCNA
  • Linux VendorLinux Affected 6.4 and later Fixed in 6.6.102, 6.12.42, 6.15.10, 6.16.1, 6.17 Patch available CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*6.4 to before 6.6.102; 6.7 to before 6.12.42; 6.13 to before 6.15.10; 6.16 to before 6.16.1VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.17:rc1:*:*:*:*:*:*6.17 rc1VulnerableLinux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 6.4 to before 6.6.102; 6.7 to before 6.12.42; 6.13 to before 6.15.10; 6.16 to before 6.16.1 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.17:rc1:*:*:*:*:*:* Versions 6.17 rc1 Vulnerable ·Linux

Remediation

  • Fix · CNA Linux (Linux) Fixed in 6.6.102, 6.12.42, 6.15.10, 6.16.1, 6.17

Red Hat 4 advisories

  • RHSA-2025:21112 Released 2025-11-12 · Red Hat rating Moderate
    kernel security update
    • Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-611.7.1.el9_7, kernel-64k-debug-devel-matched-5.14.0-611.7.1.el9_7, kernel-64k-devel-5.14.0-611.7.1.el9_7 +12
    • Red Hat Enterprise Linux BaseOS (v. 9) kernel-5.14.0-611.7.1.el9_7, kernel-64k-5.14.0-611.7.1.el9_7, kernel-64k-core-5.14.0-611.7.1.el9_7 +28
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) kernel-tools-libs-devel-5.14.0-611.7.1.el9_7, libperf-5.14.0-611.7.1.el9_7
    • Red Hat Enterprise Linux Real Time (v. 9) kernel-rt-5.14.0-611.7.1.el9_7, kernel-rt-64k-5.14.0-611.7.1.el9_7, kernel-rt-64k-core-5.14.0-611.7.1.el9_7 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 9) kernel-rt-5.14.0-611.7.1.el9_7, kernel-rt-core-5.14.0-611.7.1.el9_7, kernel-rt-debug-5.14.0-611.7.1.el9_7 +9
  • RHSA-2025:18281 Released 2025-10-20 · Red Hat rating Moderate
    kernel security update
    • Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-570.55.1.el9_6, kernel-64k-debug-devel-matched-5.14.0-570.55.1.el9_6, kernel-64k-devel-5.14.0-570.55.1.el9_6 +12
    • Red Hat Enterprise Linux BaseOS (v. 9) kernel-5.14.0-570.55.1.el9_6, kernel-64k-5.14.0-570.55.1.el9_6, kernel-64k-core-5.14.0-570.55.1.el9_6 +28
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) kernel-tools-libs-devel-5.14.0-570.55.1.el9_6, libperf-5.14.0-570.55.1.el9_6
    • Red Hat Enterprise Linux Real Time (v. 9) kernel-rt-5.14.0-570.55.1.el9_6, kernel-rt-64k-5.14.0-570.55.1.el9_6, kernel-rt-64k-core-5.14.0-570.55.1.el9_6 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 9) kernel-rt-5.14.0-570.55.1.el9_6, kernel-rt-core-5.14.0-570.55.1.el9_6, kernel-rt-debug-5.14.0-570.55.1.el9_6 +11
  • RHSA-2025:17958 Released 2025-10-14 · Red Hat rating Moderate
    kernel security update
    • Red Hat CodeReady Linux Builder EUS (v.9.4) kernel-tools-libs-devel-5.14.0-427.94.1.el9_4, libperf-5.14.0-427.94.1.el9_4
    • Red Hat Enterprise Linux AppStream EUS (v.9.4) kernel-64k-debug-devel-5.14.0-427.94.1.el9_4, kernel-64k-debug-devel-matched-5.14.0-427.94.1.el9_4, kernel-64k-devel-5.14.0-427.94.1.el9_4 +11
    • Red Hat Enterprise Linux BaseOS EUS (v.9.4) bpftool-7.3.0-427.94.1.el9_4, kernel-5.14.0-427.94.1.el9_4, kernel-64k-5.14.0-427.94.1.el9_4 +29
    • Red Hat Enterprise Linux Real Time EUS (v.9.4) kernel-rt-5.14.0-427.94.1.el9_4, kernel-rt-core-5.14.0-427.94.1.el9_4, kernel-rt-debug-5.14.0-427.94.1.el9_4 +9
    • Red Hat Enterprise Linux Real Time for NFV EUS (v.9.4) kernel-rt-5.14.0-427.94.1.el9_4, kernel-rt-core-5.14.0-427.94.1.el9_4, kernel-rt-debug-5.14.0-427.94.1.el9_4 +11
Show 1 more Red Hat advisories
  • RHSA-2025:16354 Released 2025-09-22 · Red Hat rating Moderate
    kernel security update
    • Red Hat Enterprise Linux AppStream (v. 10) kernel-64k-debug-devel-6.12.0-55.34.1.el10_0, kernel-64k-debug-devel-matched-6.12.0-55.34.1.el10_0, kernel-64k-devel-6.12.0-55.34.1.el10_0 +12
    • Red Hat Enterprise Linux BaseOS (v. 10) kernel-6.12.0-55.34.1.el10_0, kernel-64k-6.12.0-55.34.1.el10_0, kernel-64k-core-6.12.0-55.34.1.el10_0 +28
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) kernel-tools-libs-devel-6.12.0-55.34.1.el10_0, libperf-6.12.0-55.34.1.el10_0
    • Red Hat Enterprise Linux Real Time (v. 10) kernel-rt-6.12.0-55.34.1.el10_0, kernel-rt-64k-6.12.0-55.34.1.el10_0, kernel-rt-64k-core-6.12.0-55.34.1.el10_0 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 10) kernel-rt-6.12.0-55.34.1.el10_0, kernel-rt-core-6.12.0-55.34.1.el10_0, kernel-rt-debug-6.12.0-55.34.1.el10_0 +11

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 9AffectedNo fix yet
Red Hat CodeReady Linux Builder EUS (v.9.4)Fixed RHSA-2025:17958
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2025:16354
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2025:18281, RHSA-2025:21112
Red Hat Enterprise Linux AppStream EUS (v.9.4)Fixed RHSA-2025:17958
Red Hat Enterprise Linux BaseOS (v. 10)Fixed RHSA-2025:16354
Red Hat Enterprise Linux BaseOS (v. 9)Fixed RHSA-2025:18281, RHSA-2025:21112
Red Hat Enterprise Linux BaseOS EUS (v.9.4)Fixed RHSA-2025:17958
Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)Fixed RHSA-2025:16354
Red Hat Enterprise Linux CodeReady Linux Builder (v. 9)Fixed RHSA-2025:18281, RHSA-2025:21112
Red Hat Enterprise Linux Real Time (v. 10)Fixed RHSA-2025:16354
Red Hat Enterprise Linux Real Time (v. 9)Fixed RHSA-2025:18281, RHSA-2025:21112
Red Hat Enterprise Linux Real Time EUS (v.9.4)Fixed RHSA-2025:17958
Red Hat Enterprise Linux Real Time for NFV (v. 10)Fixed RHSA-2025:16354
Red Hat Enterprise Linux Real Time for NFV (v. 9)Fixed RHSA-2025:18281, RHSA-2025:21112
Red Hat Enterprise Linux Real Time for NFV EUS (v.9.4)Fixed RHSA-2025:17958
Not affected: 2 products
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-38566
  2. 2026-10-03 Alias added: GHSA-64hp-5254-q6pc
  3. 2026-10-16 CISA SSVC decision points changed
  4. 2026-11-02 EPSS moved to the 50th–90th percentile

References

Patch 5

  • 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
See all 15278 →

Sources

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