7.8

CVE-2026-74470: scsi: scsi_debug: Fix REPORT ZONES alloc_len underflow OOB write

Received
AliasesUBUNTU-CVE-2026-74470DEBIAN-CVE-2026-74470
Published 15-08-2026Last modified 16-10-2026

Vulnerability summary

CVE-2026-74470 is a high (CVSS 7.8) vulnerability in linux. EPSS estimates a 0.13% chance of exploitation in the next 30 days, higher than 2.5% of scored vulnerabilities.

Priority
Routine

Not severe (CVSS 7.8, local access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
7.8/10
010
High · v3.1 (CVE.org)
EPSS score
0.13%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 5 · Related 4
USN-8886-1USN-8959-1USN-8960-1USN-8961-1USN-8963-1

Timeline

  1. 15-08-2026
    PublishedVulnerability first disclosed.
  2. 16-10-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: scsi: scsi_debug: Fix REPORT ZONES alloc_len underflow OOB write resp_report_zones() sizes the reply buffer from the CDB allocation length. The v3 fix rounds alloc_len up with ALIGN() before deriving the descriptor count: rep_max_zones = (ALIGN((u64)alloc_len, RZONES_DESC_HD) - RZONES_DESC_HD) >> ilog2(RZONES_DESC_HD); arr_len = (u64)RZONES_DESC_HD * (rep_max_zones + 1); For alloc_len in 0xFFFFFFC1..0xFFFFFFFF, ALIGN() rounds up to 0x100000000, so arr_len is 4 GB. On 32-bit, kzalloc()'s size_t is 32-bit and truncates 0x100000000 to 0; kzalloc(0) returns ZERO_SIZE_PTR, which passes the !arr check, and desc = arr + 64 is then dereferenced in the loop -> out-of-bounds write / panic. Clamp rep_max_zones to devip->nr_zones. The loop already stops at sdebug_capacity (after nr_zones zones), so a report can never hold more than nr_zones descriptors; the clamp does not change the report, it only bounds arr_len to (nr_zones + 1) * RZONES_DESC_HD, a real device property that can never reach 0x100000000.

CVSS metrics

5 scores · 4 sources · 2 versions

EPSS trend

Probability

0.13%

Chance of exploitation in the next 30 days

Percentile

3%

Versus all other CVEs

30-day change

No change 0.00 pp

From 0.13% on 06-10-2026

06-10-202605-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

No weakness data has been published for this record.

Affected systems

Version check

Known conditions: local access, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.

Ubuntu157 products
  • linuxAll versions (No fix recorded) | < 5.15.0-202.212 | < 7.0.0-42.42
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-awsAll versions (No fix recorded) | < 5.15.0-1119.126 | < 7.0.0-1016.17
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Debian2 products
  • linux< 6.1.187-1 | < 6.12.105-1 | < 7.1.8-1
  • linux-6.12< 6.12.107-1~deb12u1
Linux1 product
  • linux≥ ebacb44cb2042b90951140eda806bedad23ef554, < 7b615fc139e35c81077046df44725c532f7e2404 | ≥ 7db0e0c8190a086ef92ce5bb960836cde49540aa, < 5d3e1d006bbb543259f9e31824caadbfff6a5465 | ≥ 7db0e0c8190a086ef92ce5bb960836cde49540aa, < 49e5b25a0b74dbac595f122e5608fdce2918cc4e | ≥ 7db0e0c8190a086ef92ce5bb960836cde49540aa, < 495058429ca55ab7fcc21977b63b92907ad68066 | ≥ 7db0e0c8190a086ef92ce5bb960836cde49540aa, < 2047ed09bf13453b7d6f9431b112ec07984dd69b | ≥ 7db0e0c8190a086ef92ce5bb960836cde49540aa, < d6e6da6bc3b53231fac77ffab428da8173ee729c | ≥ 7db0e0c8190a086ef92ce5bb960836cde49540aa, < 93dde0bf2f39a0f9f57fd610aa3201ce5b753433 | c4d2d7c935a4ad20e8e726ca10499cefe4537103 | ≥ 5.15.8, < 5.15.217 | ≥ 5.10.85, < 5.11 | 5.16

3 vendors · 160 products

References

16 links
Show all 16 references