CVE-2026-43492: Linux kernel · lib/crypto: mpi: Fix integer underflow in mpi_read_raw_from_sgl()
Source GCVE Database
Not known to be exploited · CVSS 5.5 Medium.
Data as of 26 Oct 2026, 13:47 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 4% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 19 May 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
AI-suggested
A fix for this integer underflow vulnerability has been implemented in the Linux kernel. Users and administrators should apply the official kernel updates that include this fix. Since no vendor advisory or patch links are provided here, check the Linux kernel mailing lists or official repositories for the relevant patch and update guidance. No additional mitigations are specified or required beyond applying the fix.
Description
An integer underflow vulnerability in the Linux kernel's lib/crypto mpi_read_raw_from_sgl() function can cause a denial of service (DoS) by making the kernel spin indefinitely, leading to soft lockup crashes. The flaw occurs when a scatterlist with more bytes than the nbytes parameter, filled with zeroes, triggers an underflow during subtraction. This vulnerability was introduced by a change in how scatterlists are handled in asymmetric key encryption operations and can be triggered via a specific KEYCTL_PKEY_ENCRYPT system call scenario. A fix has been implemented to address this issue.
References
- nvd.nist.gov/vuln/detail/CVE-2026-43492 (opens in a new tab)
- git.kernel.org/stable/c/1abd50fc3cfa16fc2074a3c8c2729c50fd9d7043 (opens in a new tab)
- git.kernel.org/stable/c/26d3a97ad46c7a9226ec04d4bf35bd4998a97d16 (opens in a new tab)
- git.kernel.org/stable/c/2aa77a18dc7f2670497fe3ee5acbeda0b57659e5 (opens in a new tab)
- git.kernel.org/stable/c/30e513e755bb381afce6fb57cdc8694136193f22 (opens in a new tab)
- git.kernel.org/stable/c/6d63615c796c085b4984e3031b9fa77fffb47360 (opens in a new tab)
- git.kernel.org/stable/c/8637dfb4c1d8a7026ef681f2477c6de8b71c4003 (opens in a new tab)
- git.kernel.org/stable/c/8c2f1288250a90a4b5cabed5d888d7e3aeed4035 (opens in a new tab)
- git.kernel.org/stable/c/a1793a48881ec8d26e9c79b0ee65753f1c6846a4 (opens in a new tab)
- cert-portal.siemens.com/productcert/html/ssa-019113.html (opens in a new tab)