Reference page — cumulative record through Sunday, October 4, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.
AV AC PR UI S C I A CVSS EPSS %ile KEV L L L N U N N H 5.5 .0017 5.3 —
AFFECTED Product Versions Fixed Linux 2d4d1eea540b27c72488fd1914674c42473d53df – — Linux 4.4 – 5.10.259
TIMELINE May 1 Reserved by Linux May 19 Published (CNA: Linux) Sep 8 ENRICHED — CVE-2026-43492 (Linux). Received CVSS 5.5 and CPE data from NVD.
In the Linux kernel, the following vulnerability has been resolved: lib/crypto: mpi: Fix integer underflow in mpi_read_raw_from_sgl() Yiming reports an integer underflow in mpi_read_raw_from_sgl() when subtracting "lzeros" from the unsigned "nbytes". For this to happen, the scatterlist "sgl" needs to occupy more bytes than the "nbytes" parameter and the first "nbytes + 1" bytes of the scatterlist must be zero. Under these conditions, the while loop iterating over the scatterlist will count more zeroes than "nbytes", subtract the number of zeroes from "nbytes" and cause the underflow. When commit 2d4d1eea540b ("lib/mpi: Add mpi sgl helpers") originally introduced the bug, it couldn't be triggered because all callers of mpi_read_raw_from_sgl() passed a scatterlist whose length was equal to "nbytes". However since commit 63ba4d67594a ("KEYS: asymmetric: Use new crypto interface without scatterlists"), the underflow can now actually be triggered. When invoking a KEYCTL_PKEY_ENCRYPT system call with a larger "out_len" than "in_len" and filling the "in" buffer with zeroes, crypto_akcipher_sync_prep() will create an all-zero scatterlist used for both the "src" and "dst" member of struct akcipher_request and thereby fulfil the conditions to trigger the bug: sys_keyctl() keyctl_pkey_e_d_s() asymmetric_key_eds_op() software_key_eds_op() crypto_akcipher_sync_encrypt() crypto_akcipher_sync_prep() crypto_akcipher_encrypt() rsa_enc() mpi_read_raw_from_sgl() To the user this will be visible as a DoS as the kernel spins forever, causing soft lockup splats as a side effect. Fix it.
| Date | Event | Detail |
|---|---|---|
| May 1, 2026 | Reserved | Reserved by Linux |
| May 19, 2026 | Published | Published (CNA: Linux) |
| September 8, 2026 | ENRICHED | ENRICHED — CVE-2026-43492 (Linux). Received CVSS 5.5 and CPE data from NVD. |
Authoritative record: CVE-2026-43492 at cve.org
Vendors: linux
Weaknesses: CWE-190
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-43492 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Sunday, October 4, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.
