CVE-2026-53186
CVE-2026-53186 is a critical-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 9.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.
Key facts
- Severity: Critical (CVSS 3.x base score 9.1)
- EPSS exploit prediction: 1% (42nd percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2026-39277
- Affected product: Linux Linux Kernel
- Published:
- Last modified:
Description
In the Linux kernel, the following vulnerability has been resolved: RDMA/srp: bound SRP_RSP sense copy by the received length srp_process_rsp() copies sense data from rsp->data + resp_data_len, where resp_data_len is the full 32-bit value supplied by the SRP target and is never checked against the number of bytes actually received (wc->byte_len). The copy length is bounded to SCSI_SENSE_BUFFERSIZE, so at most 96 bytes are copied, but the source offset is not bounded. A malicious or compromised SRP target on the InfiniBand/RoCE fabric that the initiator has logged into can return an SRP_RSP with SRP_RSP_FLAG_SNSVALID set and a large resp_data_len. The receive buffer is allocated at the target-chosen max_ti_iu_len, so the source of the sense copy lands past the bytes actually received; with resp_data_len near 0xFFFFFFFF it is gigabytes past the buffer and the read faults. Copy the sense data only if it has not been truncated, that is, only if the response header, the response data, and the sense region fit within the bytes actually received; otherwise drop the sense and log. The in-tree iSER and NVMe-RDMA receive paths already bound their parse by wc->byte_len; this brings ib_srp into line with them.
Frequently asked questions
- What is CVE-2026-53186?
- In the Linux kernel, the following vulnerability has been resolved: RDMA/srp: bound SRP_RSP sense copy by the received length srp_process_rsp() copies sense data from rsp->data + resp_data_len, where resp_data_len is the full 32-bit value supplied by the SRP target and is never checked against the number of bytes actually received (wc->byte_len). The copy length is bounded to SCSI_SENSE_BUFFERSIZE, so at most 96 bytes are copied, but the source offset is not bounded. A malicious or compromised SRP target on the InfiniBand/RoCE fabric that the initiator has logged into can return an SRP_RSP with SRP_RSP_FLAG_SNSVALID set and a large resp_data_len. The receive buffer is allocated at the target-chosen max_ti_iu_len, so the source of the sense copy lands past the bytes actually received; with resp_data_len near 0xFFFFFFFF it is gigabytes past the buffer and the read faults. Copy the sense data only if it has not been truncated, that is, only if the response header, the response data, and the sense region fit within the bytes actually received; otherwise drop the sense and log. The in-tree iSER and NVMe-RDMA receive paths already bound their parse by wc->byte_len; this brings ib_srp into line with them.
- How severe is CVE-2026-53186?
- CVE-2026-53186 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability high.
- Is CVE-2026-53186 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (42nd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2026-53186?
- CVE-2026-53186 primarily affects Linux Linux Kernel. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2026-53186?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
- Does CVE-2026-53186 have an EU (EUVD) identifier?
- Yes. CVE-2026-53186 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-39277.
- When was CVE-2026-53186 published?
- CVE-2026-53186 was published on 2026-06-25 and last updated on 2026-07-06.
References
- https://git.kernel.org/stable/c/0b9ee09d5e849591f17d98c078033dadea967293
- https://git.kernel.org/stable/c/0d64bc200ebe4f275b27438c6e593903e0b16fe1
- https://git.kernel.org/stable/c/13e91fd076306f5d0cdfa14f53d69e37274723c4
- https://git.kernel.org/stable/c/2015038195939eac54a1ee83c9d98ef1a8ccbbce
- https://git.kernel.org/stable/c/3523e53ff95f1837ec3f57ff7558532bcb2661b7
- https://git.kernel.org/stable/c/3889517c2ec7f364914aea8209abfff735f7ecde
- https://git.kernel.org/stable/c/ed77cc819ad631264787cade5ae5ec4c535ec6bb
- https://git.kernel.org/stable/c/f92a285db7ff6e598591ccbfb551be155c5f4d57
Affected products (8)
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:7.1:rc5:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:7.1:rc6:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:7.1:rc7:*:*:*:*:*:*
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