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TI-2025-26636 Aliases CVE-2025-39964GHSA-wr5g-mfhw-rpfj

crypto: af_alg - Disallow concurrent writes in af_alg_sendmsg

Priority CRITICAL 93Exploited in the wildCWE-362Published · 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
Fixed

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: crypto: af_alg - Disallow concurrent writes in af_alg_sendmsg Issuing two writes to the same af_alg socket is bogus as the data will be interleaved in an unpredictable fashion. Furthermore, concurrent writes may create inconsistencies in the internal socket state. Disallow this by adding a new ctx->write field that indiciates exclusive ownership for writing.

Why it matters now

Exploitation Active In CISA KEV since 2026-09-18CISA due date 2026-09-21
EPSS 0.01607 76th percentileScored 2026-11-07
Fix Fixed Linux (Linux): 5.10.245, 5.15.194, 6.1.154 +4Red Hat: 16 advisories

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Active
Automatable
No
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
LinuxLinux2.6.38 and later5.10.245, 5.15.194, 6.1.154, 6.6.108, 6.12.49, 6.16.9, 6.17Patch availableCNA
  • Linux VendorLinux Affected 2.6.38 and later Fixed in 5.10.245, 5.15.194, 6.1.154, 6.6.108, 6.12.49, 6.16.9, 6.17 Patch available CNA

CPE configurations NVD · 11

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*2.6.38 to before 5.10.245; 5.11 to before 5.15.194; 5.16 to before 6.1.154; 6.2 to before 6.6.108; 6.7 to before 6.12.49; 6.13 to before 6.16.9VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.17:rc1:*:*:*:*:*:*6.17 rc1VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.17:rc2:*:*:*:*:*:*6.17 rc2VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.17:rc3:*:*:*:*:*:*6.17 rc3VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.17:rc4:*:*:*:*:*:*6.17 rc4VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.17:rc5:*:*:*:*:*:*6.17 rc5VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.17:rc6:*:*:*:*:*:*6.17 rc6VulnerableLinux
cpe:2.3:o:siemens:simatic_s7-1500_cpu_1518-4_pn\/dp_mfp_firmware:*:*:*:*:*:*:*:*3.1.6VulnerableSiemens
cpe:2.3:h:siemens:simatic_s7-1500_cpu_1518-4_pn\/dp_mfp:*:*:*:*:*:*:*:*all versionsRunning onSiemens
cpe:2.3:o:siemens:simatic_s7-1500_cpu_1518f-4_pn\/dp_mfp_firmware:*:*:*:*:*:*:*:*3.1.6VulnerableSiemens
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 2.6.38 to before 5.10.245; 5.11 to before 5.15.194; 5.16 to before 6.1.154; 6.2 to before 6.6.108; 6.7 to before 6.12.49; 6.13 to before 6.16.9 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.17:rc1:*:*:*:*:*:* Versions 6.17 rc1 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.17:rc2:*:*:*:*:*:* Versions 6.17 rc2 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.17:rc3:*:*:*:*:*:* Versions 6.17 rc3 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.17:rc4:*:*:*:*:*:* Versions 6.17 rc4 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.17:rc5:*:*:*:*:*:* Versions 6.17 rc5 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.17:rc6:*:*:*:*:*:* Versions 6.17 rc6 Vulnerable ·Linux
  • cpe:2.3:o:siemens:simatic_s7-1500_cpu_1518-4_pn\/dp_mfp_firmware:*:*:*:*:*:*:*:* Versions 3.1.6 Vulnerable ·Siemens
  • cpe:2.3:h:siemens:simatic_s7-1500_cpu_1518-4_pn\/dp_mfp:*:*:*:*:*:*:*:* Versions all versions Running on ·Siemens
  • cpe:2.3:o:siemens:simatic_s7-1500_cpu_1518f-4_pn\/dp_mfp_firmware:*:*:*:*:*:*:*:* Versions 3.1.6 Vulnerable ·Siemens
Show 1 more CPE
CPEVersionsRoleVendor
cpe:2.3:h:siemens:simatic_s7-1500_cpu_1518f-4_pn\/dp_mfp:*:*:*:*:*:*:*:*all versionsRunning onSiemens
  • cpe:2.3:h:siemens:simatic_s7-1500_cpu_1518f-4_pn\/dp_mfp:*:*:*:*:*:*:*:* Versions all versions Running on ·Siemens

Remediation

  • Fix · CNA Linux (Linux) Fixed in 5.10.245, 5.15.194, 6.1.154, 6.6.108, 6.12.49, 6.16.9, 6.17

Red Hat 16 advisories

  • RHSA-2026:73788 Released 2026-09-30 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • NVIDIA for RHEL 10 kernel-6.12.0-259.27.el10nv, kernel-64k-6.12.0-259.27.el10nv, kernel-64k-core-6.12.0-259.27.el10nv +38
  • RHSA-2026:72059 Released 2026-09-25 · Red Hat rating Critical
    kernel security update
    • NVIDIA for RHEL 10 kernel-6.12.0-231.20.el10nv, kernel-64k-6.12.0-231.20.el10nv, kernel-64k-core-6.12.0-231.20.el10nv +38
  • RHSA-2026:71687 Released 2026-09-24 · Red Hat rating Important
    kernel security update
    • Red Hat Enterprise Linux Server (v. 7 ELS) bpftool-3.10.0-1160.164.1.el7, kernel-3.10.0-1160.164.1.el7, kernel-abi-whitelists-3.10.0-1160.164.1.el7 +11
    • Red Hat Enterprise Linux Server Optional (v. 7 ELS) kernel-debug-devel-3.10.0-1160.164.1.el7, kernel-tools-libs-devel-3.10.0-1160.164.1.el7
Show 13 more Red Hat advisories
  • RHSA-2026:71657 Released 2026-09-24 · Red Hat rating Important
    kernel-rt security update
    • Red Hat Enterprise Linux for Real Time (v. 7 ELS) kernel-rt-3.10.0-1160.164.1.rt56.1316.el7, kernel-rt-debug-3.10.0-1160.164.1.rt56.1316.el7, kernel-rt-debug-devel-3.10.0-1160.164.1.rt56.1316.el7 +4
  • RHSA-2026:71569 Released 2026-09-24 · Red Hat rating Important
    kernel security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.4) kernel-64k-debug-devel-5.14.0-427.152.1.el9_4, kernel-64k-debug-devel-matched-5.14.0-427.152.1.el9_4, kernel-64k-devel-5.14.0-427.152.1.el9_4 +11
    • Red Hat Enterprise Linux BaseOS E4S (v.9.4) bpftool-7.3.0-427.152.1.el9_4, kernel-5.14.0-427.152.1.el9_4, kernel-64k-5.14.0-427.152.1.el9_4 +29
    • Red Hat Enterprise Linux Real Time E4S (v.9.4) kernel-rt-5.14.0-427.152.1.el9_4, kernel-rt-core-5.14.0-427.152.1.el9_4, kernel-rt-debug-5.14.0-427.152.1.el9_4 +9
    • Red Hat Enterprise Linux Real Time for NFV E4S (v.9.4) kernel-rt-5.14.0-427.152.1.el9_4, kernel-rt-core-5.14.0-427.152.1.el9_4, kernel-rt-debug-5.14.0-427.152.1.el9_4 +11
  • RHSA-2026:71601 Released 2026-09-24 · Red Hat rating Important
    kernel security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.2) kernel-64k-debug-devel-5.14.0-284.194.1.el9_2, kernel-64k-debug-devel-matched-5.14.0-284.194.1.el9_2, kernel-64k-devel-5.14.0-284.194.1.el9_2 +10
    • Red Hat Enterprise Linux BaseOS E4S (v.9.2) bpftool-7.0.0-284.194.1.el9_2, kernel-5.14.0-284.194.1.el9_2, kernel-64k-5.14.0-284.194.1.el9_2 +29
  • RHSA-2026:71594 Released 2026-09-24 · Red Hat rating Important
    kernel security update
    • Red Hat Enterprise Linux BaseOS E4S (v.8.8) bpftool-4.18.0-477.170.1.el8_8, kernel-4.18.0-477.170.1.el8_8, kernel-abi-stablelists-4.18.0-477.170.1.el8_8 +14
    • Red Hat Enterprise Linux BaseOS TUS (v.8.8) bpftool-4.18.0-477.170.1.el8_8, kernel-4.18.0-477.170.1.el8_8, kernel-abi-stablelists-4.18.0-477.170.1.el8_8 +14
  • RHSA-2026:71606 Released 2026-09-24 · Red Hat rating Important
    kernel-rt security update
    • Red Hat Enterprise Linux Real Time E4S (v.9.2) kernel-rt-5.14.0-284.194.1.rt14.479.el9_2, kernel-rt-core-5.14.0-284.194.1.rt14.479.el9_2, kernel-rt-debug-5.14.0-284.194.1.rt14.479.el9_2 +9
    • Red Hat Enterprise Linux Real Time for NFV E4S (v.9.2) kernel-rt-5.14.0-284.194.1.rt14.479.el9_2, kernel-rt-core-5.14.0-284.194.1.rt14.479.el9_2, kernel-rt-debug-5.14.0-284.194.1.rt14.479.el9_2 +11
  • RHSA-2026:71592 Released 2026-09-24 · Red Hat rating Important
    kernel security update
    • Red Hat Enterprise Linux BaseOS AUS (v.8.6) bpftool-4.18.0-372.218.1.el8_6, kernel-4.18.0-372.218.1.el8_6, kernel-abi-stablelists-4.18.0-372.218.1.el8_6 +14
    • Red Hat Enterprise Linux BaseOS EUS EXTENSION (v.8.6) bpftool-4.18.0-372.218.1.el8_6, kernel-4.18.0-372.218.1.el8_6, kernel-abi-stablelists-4.18.0-372.218.1.el8_6 +19
  • RHSA-2026:71565 Released 2026-09-24 · Red Hat rating Important
    kernel security update
    • Red Hat Enterprise Linux BaseOS AUS (v.8.4) bpftool-4.18.0-305.209.1.el8_4, kernel-4.18.0-305.209.1.el8_4, kernel-abi-stablelists-4.18.0-305.209.1.el8_4 +14
    • Red Hat Enterprise Linux BaseOS EUS EXTENSION (v.8.4) bpftool-4.18.0-305.209.1.el8_4, kernel-4.18.0-305.209.1.el8_4, kernel-abi-stablelists-4.18.0-305.209.1.el8_4 +19
  • RHSA-2026:71327 Released 2026-09-24 · Red Hat rating Important
    kernel security update
    • Red Hat CodeReady Linux Builder EUS (v.9.6) kernel-tools-libs-devel-5.14.0-570.143.1.el9_6, libperf-5.14.0-570.143.1.el9_6
    • Red Hat Enterprise Linux AppStream EUS (v.9.6) kernel-64k-debug-devel-5.14.0-570.143.1.el9_6, kernel-64k-debug-devel-matched-5.14.0-570.143.1.el9_6, kernel-64k-devel-5.14.0-570.143.1.el9_6 +12
    • Red Hat Enterprise Linux BaseOS EUS (v.9.6) kernel-5.14.0-570.143.1.el9_6, kernel-64k-5.14.0-570.143.1.el9_6, kernel-64k-core-5.14.0-570.143.1.el9_6 +28
    • Red Hat Enterprise Linux Real Time EUS (v.9.6) kernel-rt-5.14.0-570.143.1.el9_6, kernel-rt-64k-5.14.0-570.143.1.el9_6, kernel-rt-64k-core-5.14.0-570.143.1.el9_6 +21
    • Red Hat Enterprise Linux Real Time for NFV EUS (v.9.6) kernel-rt-5.14.0-570.143.1.el9_6, kernel-rt-core-5.14.0-570.143.1.el9_6, kernel-rt-debug-5.14.0-570.143.1.el9_6 +11
  • RHSA-2026:71326 Released 2026-09-24 · Red Hat rating Important
    kernel security update
    • Red Hat Enterprise Linux AppStream EUS (v. 10.0) kernel-64k-debug-devel-6.12.0-55.106.1.el10_0, kernel-64k-debug-devel-matched-6.12.0-55.106.1.el10_0, kernel-64k-devel-6.12.0-55.106.1.el10_0 +12
    • Red Hat Enterprise Linux BaseOS EUS (v. 10.0) kernel-6.12.0-55.106.1.el10_0, kernel-64k-6.12.0-55.106.1.el10_0, kernel-64k-core-6.12.0-55.106.1.el10_0 +28
    • Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0) kernel-tools-libs-devel-6.12.0-55.106.1.el10_0, libperf-6.12.0-55.106.1.el10_0
    • Red Hat Enterprise Linux Real Time EUS (v. 10.0) kernel-rt-6.12.0-55.106.1.el10_0, kernel-rt-64k-6.12.0-55.106.1.el10_0, kernel-rt-64k-core-6.12.0-55.106.1.el10_0 +21
    • Red Hat Enterprise Linux Real Time for NFV EUS (v. 10.0) kernel-rt-6.12.0-55.106.1.el10_0, kernel-rt-core-6.12.0-55.106.1.el10_0, kernel-rt-debug-6.12.0-55.106.1.el10_0 +11
  • RHSA-2026:70459 Released 2026-09-23 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-687.50.1.el9_8, kernel-64k-debug-devel-matched-5.14.0-687.50.1.el9_8, kernel-64k-devel-5.14.0-687.50.1.el9_8 +12
    • Red Hat Enterprise Linux BaseOS (v. 9) kernel-5.14.0-687.50.1.el9_8, kernel-64k-5.14.0-687.50.1.el9_8, kernel-64k-core-5.14.0-687.50.1.el9_8 +28
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) kernel-tools-libs-devel-5.14.0-687.50.1.el9_8, libperf-5.14.0-687.50.1.el9_8
    • Red Hat Enterprise Linux Real Time (v. 9) kernel-rt-5.14.0-687.50.1.el9_8, kernel-rt-64k-5.14.0-687.50.1.el9_8, kernel-rt-64k-core-5.14.0-687.50.1.el9_8 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 9) kernel-rt-5.14.0-687.50.1.el9_8, kernel-rt-core-5.14.0-687.50.1.el9_8, kernel-rt-debug-5.14.0-687.50.1.el9_8 +9
  • RHSA-2026:70498 Released 2026-09-23 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream (v. 10) kernel-64k-debug-devel-6.12.0-211.58.1.el10_2, kernel-64k-debug-devel-matched-6.12.0-211.58.1.el10_2, kernel-64k-devel-6.12.0-211.58.1.el10_2 +12
    • Red Hat Enterprise Linux BaseOS (v. 10) kernel-6.12.0-211.58.1.el10_2, kernel-64k-6.12.0-211.58.1.el10_2, kernel-64k-core-6.12.0-211.58.1.el10_2 +29
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) kernel-tools-libs-devel-6.12.0-211.58.1.el10_2, libperf-6.12.0-211.58.1.el10_2
    • Red Hat Enterprise Linux Real Time (v. 10) kernel-rt-6.12.0-211.58.1.el10_2, kernel-rt-64k-6.12.0-211.58.1.el10_2, kernel-rt-64k-core-6.12.0-211.58.1.el10_2 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 10) kernel-rt-6.12.0-211.58.1.el10_2, kernel-rt-core-6.12.0-211.58.1.el10_2, kernel-rt-debug-6.12.0-211.58.1.el10_2 +9
  • RHSA-2026:70402 Released 2026-09-22 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • Red Hat Enterprise Linux BaseOS (v. 8) bpftool-4.18.0-553.166.1.el8_10, kernel-4.18.0-553.166.1.el8_10, kernel-abi-stablelists-4.18.0-553.166.1.el8_10 +19
    • Red Hat Enterprise Linux CRB (v. 8) kernel-tools-libs-devel-4.18.0-553.166.1.el8_10
  • RHSA-2026:70403 Released 2026-09-22 · Red Hat rating Important
    kernel-rt security, bug fix, and enhancement update
    • Red Hat Enterprise Linux NFV (v. 8) kernel-rt-4.18.0-553.166.1.rt7.507.el8_10, kernel-rt-core-4.18.0-553.166.1.rt7.507.el8_10, kernel-rt-debug-4.18.0-553.166.1.rt7.507.el8_10 +9
    • Red Hat Enterprise Linux RT (v. 8) kernel-rt-4.18.0-553.166.1.rt7.507.el8_10, kernel-rt-core-4.18.0-553.166.1.rt7.507.el8_10, kernel-rt-debug-4.18.0-553.166.1.rt7.507.el8_10 +7

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
NVIDIA for RHEL 10Fixed RHSA-2026:72059, RHSA-2026:73788
Red Hat CodeReady Linux Builder EUS (v.9.6)Fixed RHSA-2026:71327
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2026:70498
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2026:70459
Red Hat Enterprise Linux AppStream E4S (v.9.2)Fixed RHSA-2026:71601
Red Hat Enterprise Linux AppStream E4S (v.9.4)Fixed RHSA-2026:71569
Red Hat Enterprise Linux AppStream EUS (v. 10.0)Fixed RHSA-2026:71326
Red Hat Enterprise Linux AppStream EUS (v.9.6)Fixed RHSA-2026:71327
Red Hat Enterprise Linux BaseOS (v. 10)Fixed RHSA-2026:70498
Red Hat Enterprise Linux BaseOS (v. 8)Fixed RHSA-2026:70402
Red Hat Enterprise Linux BaseOS (v. 9)Fixed RHSA-2026:70459
Red Hat Enterprise Linux BaseOS AUS (v.8.4)Fixed RHSA-2026:71565
Red Hat Enterprise Linux BaseOS AUS (v.8.6)Fixed RHSA-2026:71592
Red Hat Enterprise Linux BaseOS E4S (v.8.8)Fixed RHSA-2026:71594
Red Hat Enterprise Linux BaseOS E4S (v.9.2)Fixed RHSA-2026:71601
Red Hat Enterprise Linux BaseOS E4S (v.9.4)Fixed RHSA-2026:71569
Red Hat Enterprise Linux BaseOS EUS (v. 10.0)Fixed RHSA-2026:71326
Red Hat Enterprise Linux BaseOS EUS (v.9.6)Fixed RHSA-2026:71327
Red Hat Enterprise Linux BaseOS EUS EXTENSION (v.8.4)Fixed RHSA-2026:71565
Red Hat Enterprise Linux BaseOS EUS EXTENSION (v.8.6)Fixed RHSA-2026:71592
Red Hat Enterprise Linux BaseOS TUS (v.8.8)Fixed RHSA-2026:71594
Red Hat Enterprise Linux CRB (v. 8)Fixed RHSA-2026:70402
Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)Fixed RHSA-2026:70498
Red Hat Enterprise Linux CodeReady Linux Builder (v. 9)Fixed RHSA-2026:70459
Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0)Fixed RHSA-2026:71326
Red Hat Enterprise Linux NFV (v. 8)Fixed RHSA-2026:70403
Red Hat Enterprise Linux RT (v. 8)Fixed RHSA-2026:70403
Red Hat Enterprise Linux Real Time (v. 10)Fixed RHSA-2026:70498
Red Hat Enterprise Linux Real Time (v. 9)Fixed RHSA-2026:70459
Red Hat Enterprise Linux Real Time E4S (v.9.2)Fixed RHSA-2026:71606
Red Hat Enterprise Linux Real Time E4S (v.9.4)Fixed RHSA-2026:71569
Red Hat Enterprise Linux Real Time EUS (v. 10.0)Fixed RHSA-2026:71326
Red Hat Enterprise Linux Real Time EUS (v.9.6)Fixed RHSA-2026:71327
Red Hat Enterprise Linux Real Time for NFV (v. 10)Fixed RHSA-2026:70498
Red Hat Enterprise Linux Real Time for NFV (v. 9)Fixed RHSA-2026:70459
Red Hat Enterprise Linux Real Time for NFV E4S (v.9.2)Fixed RHSA-2026:71606
Red Hat Enterprise Linux Real Time for NFV E4S (v.9.4)Fixed RHSA-2026:71569
Red Hat Enterprise Linux Real Time for NFV EUS (v. 10.0)Fixed RHSA-2026:71326
Red Hat Enterprise Linux Real Time for NFV EUS (v.9.6)Fixed RHSA-2026:71327
Red Hat Enterprise Linux Server (v. 7 ELS)Fixed RHSA-2026:71687
Red Hat Enterprise Linux Server Optional (v. 7 ELS)Fixed RHSA-2026:71687
Red Hat Enterprise Linux for Real Time (v. 7 ELS)Fixed RHSA-2026:71657
Not affected: 1 product
  • Red Hat Enterprise Linux 6

Timeline

  1. 2026-09-18 Added to CISA KEV
  2. 2026-10-02 Threatist record created from CVE-2025-39964
  3. 2026-10-03 Alias added: GHSA-wr5g-mfhw-rpfj
  4. 2026-10-16 Affected versions changed · Red Hat

References

  • 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