CVE-2026-80951i3c: master: svc: bound IBI payload to the requested max_payload_len
- —Not scoredno CVSS score yet
- 0.21%Exploitation in 30 daysEPSS · top 89% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
In the Linux kernel, the following vulnerability has been resolved: i3c: master: svc: bound IBI payload to the requested max_payload_len svc_i3c_master_handle_ibi() reads the IBI payload from the RX FIFO into the IBI slot. The loop is bounded by the hardware FIFO size (SVC_I3C_FIFO_SIZE), not by the slot size. slot->data points into the IBI pool, which i3c_generic_ibi_alloc_pool() sizes at max_payload_len per slot. svc_i3c_master_request_ibi() only rejects a max_payload_len larger than SVC_I3C_FIFO_SIZE, so a driver can request a smaller one. mctp-i3c requests 1. Each readsb() then copies the controller RXCOUNT bytes (up to 31) with no check against the slot size. A device that sends more bytes than the slot holds writes past slot->data, an out-of-bounds write into the IBI pool. Bound the loop by dev->ibi->max_payload_len and clamp each read to the space left in the slot, the same way dw-i3c does. A device can still send more than the requested payload. Flush the leftover bytes from the RX FIFO so they do not leak into the next transfer.
Timeline
ID reserved
By Linux
- 16 days later
· 16 days later
Published
- 38 days later
· 38 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
No CVSS score yet: neither the CNA, CISA nor NVD has scored this CVE. NVD status: Received.
- EPSS (exploitation in 30 days)
- 0.21% · top 89% of all CVEs (12 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Not scored.
Affected products
- affected dd3c52846d5954acd43f0e771689302f27dadc28 – < 7c099b0b292a68d0ef558527945dbfb756fbf893
- affected dd3c52846d5954acd43f0e771689302f27dadc28 – < 7cc5ba756bc1cfffab9cb2695742f9f479dc73f7
- affected dd3c52846d5954acd43f0e771689302f27dadc28 – < 35aa6730b8c5626b879a4e893fe664f59bf07d7f
- affected dd3c52846d5954acd43f0e771689302f27dadc28 – < f296a0d5907bf88314dfda67245f7f69d1552470
- affected dd3c52846d5954acd43f0e771689302f27dadc28 – < 5697d779577e2786ff3348ae9b77020ac0cf0aab
- affected dd3c52846d5954acd43f0e771689302f27dadc28 – < aac3c5aababc7fb69d5bf5b0cc52d308574e3a8c
- affected dd3c52846d5954acd43f0e771689302f27dadc28 – < e2bda39d7f9f285ec803e200b5c1f17143d0b483
- affected 5.12
- unaffected < 5.12
- unaffected 5.15.221 – ≤ 5.15.*
- unaffected 6.1.188 – ≤ 6.1.*
- unaffected 6.6.157 – ≤ 6.6.*
- unaffected 6.12.109 – ≤ 6.12.*
- unaffected 6.18.50 – ≤ 6.18.*
- unaffected 7.2.4 – ≤ 7.2.*
- unaffected 7.3 – ≤ *
References
References7
- https://git.kernel.org/stable/c/7c099b0b292a68d0ef558527945dbfb756fbf893 (opens in a new tab)
- https://git.kernel.org/stable/c/7cc5ba756bc1cfffab9cb2695742f9f479dc73f7 (opens in a new tab)
- https://git.kernel.org/stable/c/35aa6730b8c5626b879a4e893fe664f59bf07d7f (opens in a new tab)
- https://git.kernel.org/stable/c/f296a0d5907bf88314dfda67245f7f69d1552470 (opens in a new tab)
- https://git.kernel.org/stable/c/5697d779577e2786ff3348ae9b77020ac0cf0aab (opens in a new tab)
- https://git.kernel.org/stable/c/aac3c5aababc7fb69d5bf5b0cc52d308574e3a8c (opens in a new tab)
- https://git.kernel.org/stable/c/e2bda39d7f9f285ec803e200b5c1f17143d0b483 (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-76274 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-80951)Record last updated .