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TI-2026-38262 Aliases CVE-2026-53176GHSA-cm56-mvx6-66qm

IB/isert: Reject login PDUs shorter than ISER_HEADERS_LEN

Priority MEDIUM 50CWE-839Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 14 fixed, 2 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-191 and the CVSS impact.

Summary

In the Linux kernel, the following vulnerability has been resolved: IB/isert: Reject login PDUs shorter than ISER_HEADERS_LEN In drivers/infiniband/ulp/isert/ib_isert.c, isert_login_recv_done() computes the login request payload length as wc->byte_len minus ISER_HEADERS_LEN with no lower bound, and login_req_len is a signed int. A remote iSER initiator can post a login Send work request carrying fewer than ISER_HEADERS_LEN (76) bytes, so the subtraction underflows and login_req_len becomes negative. isert_rx_login_req() then reads that negative length back into a signed int, takes size = min(rx_buflen, MAX_KEY_VALUE_PAIRS), and because the min() is signed it keeps the negative value; the value is then passed as the memcpy() length and sign-extended to a multi-gigabyte size_t. The copy into the 8192-byte login->req_buf runs far out of bounds and faults, crashing the target node. The login phase precedes iSCSI authentication, so no credentials are required to reach this path. Reject any login PDU shorter than ISER_HEADERS_LEN before the subtraction, mirroring the existing early return on a failed work completion, so login_req_len can never go negative. The upper bound was already safe: a posted login buffer cannot deliver more than ISER_RX_PAYLOAD_SIZE, so the difference stays at or below MAX_KEY_VALUE_PAIRS and the existing min() clamps it; only the missing lower bound needs to be added.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00761 55th percentileScored 2026-11-07
Fix Partial Linux (Linux): 5.10.259, 5.15.210, 6.1.176 +5Red Hat: 4 advisoriesRed Hat: 14 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
LinuxLinux3.10 and later5.10.259, 5.15.210, 6.1.176, 6.6.143, 6.12.94, 6.18.36, 7.0.13, 7.1Patch availableCNA
  • Linux VendorLinux Affected 3.10 and later Fixed in 5.10.259, 5.15.210, 6.1.176, 6.6.143, 6.12.94, 6.18.36, 7.0.13, 7.1 Patch available CNA

CPE configurations NVD · 8

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*3.10 to before 5.10.259; 5.11 to before 5.15.210; 5.16 to before 6.1.176; 6.2 to before 6.6.143; 6.7 to before 6.12.94; 6.13 to before 6.18.36; 6.19 to before 7.0.13VulnerableLinux
cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:*7.1 rc1VulnerableLinux
cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:*7.1 rc2VulnerableLinux
cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:*7.1 rc3VulnerableLinux
cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:*7.1 rc4VulnerableLinux
cpe:2.3:o:linux:linux_kernel:7.1:rc5:*:*:*:*:*:*7.1 rc5VulnerableLinux
cpe:2.3:o:linux:linux_kernel:7.1:rc6:*:*:*:*:*:*7.1 rc6VulnerableLinux
cpe:2.3:o:linux:linux_kernel:7.1:rc7:*:*:*:*:*:*7.1 rc7VulnerableLinux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 3.10 to before 5.10.259; 5.11 to before 5.15.210; 5.16 to before 6.1.176; 6.2 to before 6.6.143; 6.7 to before 6.12.94; 6.13 to before 6.18.36; 6.19 to before 7.0.13 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:* Versions 7.1 rc1 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:* Versions 7.1 rc2 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:* Versions 7.1 rc3 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:* Versions 7.1 rc4 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:7.1:rc5:*:*:*:*:*:* Versions 7.1 rc5 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:7.1:rc6:*:*:*:*:*:* Versions 7.1 rc6 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:7.1:rc7:*:*:*:*:*:* Versions 7.1 rc7 Vulnerable ·Linux

Remediation

  • Fix · CNA Linux (Linux) Fixed in 5.10.259, 5.15.210, 6.1.176, 6.6.143, 6.12.94, 6.18.36, 7.0.13, 7.1

Red Hat 4 advisories

  • RHSA-2026:68570 Released 2026-09-17 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-687.49.1.el9_8, kernel-64k-debug-devel-matched-5.14.0-687.49.1.el9_8, kernel-64k-devel-5.14.0-687.49.1.el9_8 +12
    • Red Hat Enterprise Linux BaseOS (v. 9) kernel-5.14.0-687.49.1.el9_8, kernel-64k-5.14.0-687.49.1.el9_8, kernel-64k-core-5.14.0-687.49.1.el9_8 +28
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) kernel-tools-libs-devel-5.14.0-687.49.1.el9_8, libperf-5.14.0-687.49.1.el9_8
    • Red Hat Enterprise Linux Real Time (v. 9) kernel-rt-5.14.0-687.49.1.el9_8, kernel-rt-64k-5.14.0-687.49.1.el9_8, kernel-rt-64k-core-5.14.0-687.49.1.el9_8 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 9) kernel-rt-5.14.0-687.49.1.el9_8, kernel-rt-core-5.14.0-687.49.1.el9_8, kernel-rt-debug-5.14.0-687.49.1.el9_8 +9
  • RHSA-2026:68531 Released 2026-09-17 · Red Hat rating Important
    kernel security update
    • Red Hat Enterprise Linux BaseOS (v. 8) bpftool-4.18.0-553.164.1.el8_10, kernel-4.18.0-553.164.1.el8_10, kernel-abi-stablelists-4.18.0-553.164.1.el8_10 +19
    • Red Hat Enterprise Linux CRB (v. 8) kernel-tools-libs-devel-4.18.0-553.164.1.el8_10
  • RHSA-2026:68532 Released 2026-09-17 · Red Hat rating Important
    kernel-rt security update
    • Red Hat Enterprise Linux NFV (v. 8) kernel-rt-4.18.0-553.164.1.rt7.505.el8_10, kernel-rt-core-4.18.0-553.164.1.rt7.505.el8_10, kernel-rt-debug-4.18.0-553.164.1.rt7.505.el8_10 +9
    • Red Hat Enterprise Linux RT (v. 8) kernel-rt-4.18.0-553.164.1.rt7.505.el8_10, kernel-rt-core-4.18.0-553.164.1.rt7.505.el8_10, kernel-rt-debug-4.18.0-553.164.1.rt7.505.el8_10 +7
Show 1 more Red Hat advisories
  • RHSA-2026:68507 Released 2026-09-17 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream (v. 10) kernel-64k-debug-devel-6.12.0-211.56.1.el10_2, kernel-64k-debug-devel-matched-6.12.0-211.56.1.el10_2, kernel-64k-devel-6.12.0-211.56.1.el10_2 +12
    • Red Hat Enterprise Linux BaseOS (v. 10) kernel-6.12.0-211.56.1.el10_2, kernel-64k-6.12.0-211.56.1.el10_2, kernel-64k-core-6.12.0-211.56.1.el10_2 +29
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) kernel-tools-libs-devel-6.12.0-211.56.1.el10_2, libperf-6.12.0-211.56.1.el10_2
    • Red Hat Enterprise Linux Real Time (v. 10) kernel-rt-6.12.0-211.56.1.el10_2, kernel-rt-64k-6.12.0-211.56.1.el10_2, kernel-rt-64k-core-6.12.0-211.56.1.el10_2 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 10) kernel-rt-6.12.0-211.56.1.el10_2, kernel-rt-core-6.12.0-211.56.1.el10_2, kernel-rt-debug-6.12.0-211.56.1.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 7AffectedNo fix yet
Red Hat Enterprise Linux 9AffectedNo fix yet
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2026:68507
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2026:68570
Red Hat Enterprise Linux BaseOS (v. 10)Fixed RHSA-2026:68507
Red Hat Enterprise Linux BaseOS (v. 8)Fixed RHSA-2026:68531
Red Hat Enterprise Linux BaseOS (v. 9)Fixed RHSA-2026:68570
Red Hat Enterprise Linux CRB (v. 8)Fixed RHSA-2026:68531
Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)Fixed RHSA-2026:68507
Red Hat Enterprise Linux CodeReady Linux Builder (v. 9)Fixed RHSA-2026:68570
Red Hat Enterprise Linux NFV (v. 8)Fixed RHSA-2026:68532
Red Hat Enterprise Linux RT (v. 8)Fixed RHSA-2026:68532
Red Hat Enterprise Linux Real Time (v. 10)Fixed RHSA-2026:68507
Red Hat Enterprise Linux Real Time (v. 9)Fixed RHSA-2026:68570
Red Hat Enterprise Linux Real Time for NFV (v. 10)Fixed RHSA-2026:68507
Red Hat Enterprise Linux Real Time for NFV (v. 9)Fixed RHSA-2026:68570
Not affected: 1 product
  • Red Hat Enterprise Linux 6

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-53176
  2. 2026-10-03 Alias added: GHSA-cm56-mvx6-66qm
  3. 2026-10-16 CISA SSVC decision points changed
  4. 2026-10-19 Weakness changed · CISA ADP

References

Patch 8

Advisory 3

  • 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