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TI-2026-18677 Aliases CVE-2026-23240GHSA-c96v-vvf3-2p7r

tls: Fix race condition in tls_sw_cancel_work_tx()

Priority MEDIUM 50CWE-362Published · 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: 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: tls: Fix race condition in tls_sw_cancel_work_tx() This issue was discovered during a code audit. After cancel_delayed_work_sync() is called from tls_sk_proto_close(), tx_work_handler() can still be scheduled from paths such as the Delayed ACK handler or ksoftirqd. As a result, the tx_work_handler() worker may dereference a freed TLS object. The following is a simple race scenario: cpu0 cpu1 tls_sk_proto_close() tls_sw_cancel_work_tx() tls_write_space() tls_sw_write_space() if (!test_and_set_bit(BIT_TX_SCHEDULED, &tx_ctx->tx_bitmask)) set_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask); cancel_delayed_work_sync(&ctx->tx_work.work); schedule_delayed_work(&tx_ctx->tx_work.work, 0); To prevent this race condition, cancel_delayed_work_sync() is replaced with disable_delayed_work_sync().

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00563 47th percentileScored 2026-11-07
Fix Partial Linux (Linux): 6.12.75, 6.18.16, 6.19.6 +1Red Hat: 3 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
LinuxLinux5.3 and later6.12.75, 6.18.16, 6.19.6, 7.0Patch availableCNA
  • Linux VendorLinux Affected 5.3 and later Fixed in 6.12.75, 6.18.16, 6.19.6, 7.0 Patch available CNA

CPE configurations NVD · 8

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*5.3.1 to before 6.12.75; 6.13 to before 6.18.16; 6.19 to before 6.19.6VulnerableLinux
cpe:2.3:o:linux:linux_kernel:5.3:-:*:*:*:*:*:*5.3VulnerableLinux
cpe:2.3:o:linux:linux_kernel:5.3:rc4:*:*:*:*:*:*5.3 rc4VulnerableLinux
cpe:2.3:o:linux:linux_kernel:5.3:rc5:*:*:*:*:*:*5.3 rc5VulnerableLinux
cpe:2.3:o:linux:linux_kernel:5.3:rc6:*:*:*:*:*:*5.3 rc6VulnerableLinux
cpe:2.3:o:linux:linux_kernel:5.3:rc7:*:*:*:*:*:*5.3 rc7VulnerableLinux
cpe:2.3:o:linux:linux_kernel:5.3:rc8:*:*:*:*:*:*5.3 rc8VulnerableLinux
cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*7.0 rc1VulnerableLinux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 5.3.1 to before 6.12.75; 6.13 to before 6.18.16; 6.19 to before 6.19.6 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:5.3:-:*:*:*:*:*:* Versions 5.3 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:5.3:rc4:*:*:*:*:*:* Versions 5.3 rc4 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:5.3:rc5:*:*:*:*:*:* Versions 5.3 rc5 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:5.3:rc6:*:*:*:*:*:* Versions 5.3 rc6 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:5.3:rc7:*:*:*:*:*:* Versions 5.3 rc7 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:5.3:rc8:*:*:*:*:*:* Versions 5.3 rc8 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:* Versions 7.0 rc1 Vulnerable ·Linux

Remediation

  • Fix · CNA Linux (Linux) Fixed in 6.12.75, 6.18.16, 6.19.6, 7.0

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 10AffectedNo fix yet
Red Hat Enterprise Linux 8AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 9AffectedNo fix yet
Not affected: 2 products
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-23240
  2. 2026-10-03 Alias added: GHSA-c96v-vvf3-2p7r
  3. 2026-10-16 CISA SSVC decision points changed
  4. 2026-10-19 Weakness changed · CISA ADP
  5. 2026-10-29 Affected versions changed · Red Hat

References

Patch 4

  • 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