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TI-2025-26472 Aliases CVE-2025-39797GHSA-p94f-8hph-rvrp

xfrm: Duplicate SPI Handling

Priority LOW 33Published · 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: 24 fixed, 4 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat.

Summary

In the Linux kernel, the following vulnerability has been resolved: xfrm: Duplicate SPI Handling The issue originates when Strongswan initiates an XFRM_MSG_ALLOCSPI Netlink message, which triggers the kernel function xfrm_alloc_spi(). This function is expected to ensure uniqueness of the Security Parameter Index (SPI) for inbound Security Associations (SAs). However, it can return success even when the requested SPI is already in use, leading to duplicate SPIs assigned to multiple inbound SAs, differentiated only by their destination addresses. This behavior causes inconsistencies during SPI lookups for inbound packets. Since the lookup may return an arbitrary SA among those with the same SPI, packet processing can fail, resulting in packet drops. According to RFC 4301 section 4.4.2 , for inbound processing a unicast SA is uniquely identified by the SPI and optionally protocol. Reproducing the Issue Reliably: To consistently reproduce the problem, restrict the available SPI range in charon.conf : spi_min = 0x10000000 spi_max = 0x10000002 This limits the system to only 2 usable SPI values. Next, create more than 2 Child SA. each using unique pair of src/dst address. As soon as the 3rd Child SA is initiated, it will be assigned a duplicate SPI, since the SPI pool is already exhausted. With a narrow SPI range, the issue is consistently reproducible. With a broader/default range, it becomes rare and unpredictable. Current implementation: xfrm_spi_hash() lookup function computes hash using daddr, proto, and family. So if two SAs have the same SPI but different destination addresses, then they will: a. Hash into different buckets b. Be stored in different linked lists (byspi + h) c. Not be seen in the same hlist_for_each_entry_rcu() iteration. As a result, the lookup will result in NULL and kernel allows that Duplicate SPI Proposed Change: xfrm_state_lookup_spi_proto() does a truly global search - across all states, regardless of hash bucket and matches SPI and proto.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00161 5th percentileScored 2026-11-07
Fix Partial Linux (Linux): 6.1.191, 6.6.103, 6.12.43 +3Red Hat: 5 advisoriesRed Hat: 24 fixed, 4 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

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

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux2.6.12 and later6.1.191, 6.6.103, 6.12.43, 6.15.11, 6.16.2, 6.17Patch availableCNA
  • Linux VendorLinux Affected 2.6.12 and later Fixed in 6.1.191, 6.6.103, 6.12.43, 6.15.11, 6.16.2, 6.17 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*before 6.6.103; 6.7 to before 6.12.43; 6.13 to before 6.15.11; 6.16 to before 6.16.2VulnerableLinux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions before 6.6.103; 6.7 to before 6.12.43; 6.13 to before 6.15.11; 6.16 to before 6.16.2 Vulnerable ·Linux

Remediation

  • Fix · CNA Linux (Linux) Fixed in 6.1.191, 6.6.103, 6.12.43, 6.15.11, 6.16.2, 6.17

Red Hat 5 advisories

  • RHSA-2026:94508 Released 2026-11-03 · Red Hat rating Critical
    kernel security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream EUS (v. 10.0) kernel-64k-debug-devel-6.12.0-55.117.1.el10_0, kernel-64k-debug-devel-matched-6.12.0-55.117.1.el10_0, kernel-64k-devel-6.12.0-55.117.1.el10_0 +12
    • Red Hat Enterprise Linux BaseOS EUS (v. 10.0) kernel-6.12.0-55.117.1.el10_0, kernel-64k-6.12.0-55.117.1.el10_0, kernel-64k-core-6.12.0-55.117.1.el10_0 +28
    • Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0) kernel-tools-libs-devel-6.12.0-55.117.1.el10_0, libperf-6.12.0-55.117.1.el10_0
    • Red Hat Enterprise Linux Real Time EUS (v. 10.0) kernel-rt-6.12.0-55.117.1.el10_0, kernel-rt-64k-6.12.0-55.117.1.el10_0, kernel-rt-64k-core-6.12.0-55.117.1.el10_0 +21
    • Red Hat Enterprise Linux Real Time for NFV EUS (v. 10.0) kernel-rt-6.12.0-55.117.1.el10_0, kernel-rt-core-6.12.0-55.117.1.el10_0, kernel-rt-debug-6.12.0-55.117.1.el10_0 +11
  • RHSA-2026:91492 Released 2026-10-28 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • Red Hat CodeReady Linux Builder EUS (v.9.6) kernel-tools-libs-devel-5.14.0-570.152.1.el9_6, libperf-5.14.0-570.152.1.el9_6
    • Red Hat Enterprise Linux AppStream EUS (v.9.6) kernel-64k-debug-devel-5.14.0-570.152.1.el9_6, kernel-64k-debug-devel-matched-5.14.0-570.152.1.el9_6, kernel-64k-devel-5.14.0-570.152.1.el9_6 +12
    • Red Hat Enterprise Linux BaseOS EUS (v.9.6) kernel-5.14.0-570.152.1.el9_6, kernel-64k-5.14.0-570.152.1.el9_6, kernel-64k-core-5.14.0-570.152.1.el9_6 +28
    • Red Hat Enterprise Linux Real Time EUS (v.9.6) kernel-rt-5.14.0-570.152.1.el9_6, kernel-rt-64k-5.14.0-570.152.1.el9_6, kernel-rt-64k-core-5.14.0-570.152.1.el9_6 +21
    • Red Hat Enterprise Linux Real Time for NFV EUS (v.9.6) kernel-rt-5.14.0-570.152.1.el9_6, kernel-rt-core-5.14.0-570.152.1.el9_6, kernel-rt-debug-5.14.0-570.152.1.el9_6 +11
  • RHSA-2026:91489 Released 2026-10-28 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream E4S (v.9.4) kernel-64k-debug-devel-5.14.0-427.158.1.el9_4, kernel-64k-debug-devel-matched-5.14.0-427.158.1.el9_4, kernel-64k-devel-5.14.0-427.158.1.el9_4 +11
    • Red Hat Enterprise Linux BaseOS E4S (v.9.4) bpftool-7.3.0-427.158.1.el9_4, kernel-5.14.0-427.158.1.el9_4, kernel-64k-5.14.0-427.158.1.el9_4 +29
    • Red Hat Enterprise Linux Real Time E4S (v.9.4) kernel-rt-5.14.0-427.158.1.el9_4, kernel-rt-core-5.14.0-427.158.1.el9_4, kernel-rt-debug-5.14.0-427.158.1.el9_4 +9
    • Red Hat Enterprise Linux Real Time for NFV E4S (v.9.4) kernel-rt-5.14.0-427.158.1.el9_4, kernel-rt-core-5.14.0-427.158.1.el9_4, kernel-rt-debug-5.14.0-427.158.1.el9_4 +11
Show 2 more Red Hat advisories
  • RHSA-2026:47040 Released 2026-07-28 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-687.31.1.el9_8, kernel-64k-debug-devel-matched-5.14.0-687.31.1.el9_8, kernel-64k-devel-5.14.0-687.31.1.el9_8 +12
    • Red Hat Enterprise Linux BaseOS (v. 9) kernel-5.14.0-687.31.1.el9_8, kernel-64k-5.14.0-687.31.1.el9_8, kernel-64k-core-5.14.0-687.31.1.el9_8 +28
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) kernel-tools-libs-devel-5.14.0-687.31.1.el9_8, libperf-5.14.0-687.31.1.el9_8
    • Red Hat Enterprise Linux Real Time (v. 9) kernel-rt-5.14.0-687.31.1.el9_8, kernel-rt-64k-5.14.0-687.31.1.el9_8, kernel-rt-64k-core-5.14.0-687.31.1.el9_8 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 9) kernel-rt-5.14.0-687.31.1.el9_8, kernel-rt-core-5.14.0-687.31.1.el9_8, kernel-rt-debug-5.14.0-687.31.1.el9_8 +9
  • RHSA-2026:18134 Released 2026-05-19 · Red Hat rating Moderate
    kernel security update
    • Red Hat Enterprise Linux AppStream (v. 10) kernel-64k-debug-devel-6.12.0-211.7.1.el10_2, kernel-64k-debug-devel-matched-6.12.0-211.7.1.el10_2, kernel-64k-devel-6.12.0-211.7.1.el10_2 +12
    • Red Hat Enterprise Linux BaseOS (v. 10) kernel-6.12.0-211.7.1.el10_2, kernel-64k-6.12.0-211.7.1.el10_2, kernel-64k-core-6.12.0-211.7.1.el10_2 +29
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) kernel-tools-libs-devel-6.12.0-211.7.1.el10_2, libperf-6.12.0-211.7.1.el10_2
    • Red Hat Enterprise Linux Real Time (v. 10) kernel-rt-6.12.0-211.7.1.el10_2, kernel-rt-64k-6.12.0-211.7.1.el10_2, kernel-rt-64k-core-6.12.0-211.7.1.el10_2 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 10) kernel-rt-6.12.0-211.7.1.el10_2, kernel-rt-core-6.12.0-211.7.1.el10_2, kernel-rt-debug-6.12.0-211.7.1.el10_2 +9

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 7AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 8AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 9AffectedNo fix yet: Fix deferred
Red Hat CodeReady Linux Builder EUS (v.9.6)Fixed RHSA-2026:91492
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2026:18134
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2026:47040
Red Hat Enterprise Linux AppStream E4S (v.9.4)Fixed RHSA-2026:91489
Red Hat Enterprise Linux AppStream EUS (v. 10.0)Fixed RHSA-2026:94508
Red Hat Enterprise Linux AppStream EUS (v.9.6)Fixed RHSA-2026:91492
Red Hat Enterprise Linux BaseOS (v. 10)Fixed RHSA-2026:18134
Red Hat Enterprise Linux BaseOS (v. 9)Fixed RHSA-2026:47040
Red Hat Enterprise Linux BaseOS E4S (v.9.4)Fixed RHSA-2026:91489
Red Hat Enterprise Linux BaseOS EUS (v. 10.0)Fixed RHSA-2026:94508
Red Hat Enterprise Linux BaseOS EUS (v.9.6)Fixed RHSA-2026:91492
Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)Fixed RHSA-2026:18134
Red Hat Enterprise Linux CodeReady Linux Builder (v. 9)Fixed RHSA-2026:47040
Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0)Fixed RHSA-2026:94508
Red Hat Enterprise Linux Real Time (v. 10)Fixed RHSA-2026:18134
Red Hat Enterprise Linux Real Time (v. 9)Fixed RHSA-2026:47040
Red Hat Enterprise Linux Real Time E4S (v.9.4)Fixed RHSA-2026:91489
Red Hat Enterprise Linux Real Time EUS (v. 10.0)Fixed RHSA-2026:94508
Red Hat Enterprise Linux Real Time EUS (v.9.6)Fixed RHSA-2026:91492
Red Hat Enterprise Linux Real Time for NFV (v. 10)Fixed RHSA-2026:18134
Red Hat Enterprise Linux Real Time for NFV (v. 9)Fixed RHSA-2026:47040
Red Hat Enterprise Linux Real Time for NFV E4S (v.9.4)Fixed RHSA-2026:91489
Red Hat Enterprise Linux Real Time for NFV EUS (v. 10.0)Fixed RHSA-2026:94508
Red Hat Enterprise Linux Real Time for NFV EUS (v.9.6)Fixed RHSA-2026:91492

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-39797
  2. 2026-10-03 Alias added: GHSA-p94f-8hph-rvrp
  3. 2026-10-29 Fix available: RHSA-2026:91489 · Red Hat
  4. 2026-10-30 Fix available: RHSA-2026:91492 · Red Hat
  5. 2026-10-30 Fix available: Red Hat CodeReady Linux Builder EUS (v.9.6), Red Hat Enterprise Linux AppStream E4S (v.9.4), Red Hat Enterprise Linux AppStream EUS (v.9.6) +6 · Red Hat
  6. 2026-10-30 Fix available: Linux/[email protected], Linux/Linux@fb58962aa3b9359988c7b5b15a971fd9ad5b0ecd · CNA
  7. 2026-10-30 1 new reference · CNA
  8. 2026-11-03 Fix available: RHSA-2026:94508 · Red Hat
  9. 2026-11-03 Fix available: Red Hat Enterprise Linux AppStream EUS (v. 10.0), Red Hat Enterprise Linux BaseOS EUS (v. 10.0), Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0) +2 · Red Hat
  10. 2026-11-05 CISA SSVC decision points changed

References

Patch 5

Other 1

  • 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