What is CVE-2026-48104?

CVE-2026-48104 is a medium-severity vulnerability in 7-zip, classified under Out-of-bounds Read. CVSS score: 4.2/10. Published 2026-06-05.

How severe is CVE-2026-48104?

Medium severity. CVSS v3 base score is 4.2 out of 10.

Out-of-bounds Read in 7-zip

CVE-2026-48104

7-Zip is a file archiver with a high compression ratio. Versions 9.18 through 26.00 contain an uninitialized heap read in the SquashFS archive handler caused by a sparsely populated index array. In the SquashFS handler, _blockToNode is all…

Vulnerability class: Buffer Overflow

EPSS: 0.002 (7.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 4.2 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:L.

Affected products

7-zip
Mcmilk 7-zip — versions >= 9.18, < 26.01

Weakness classification (CWE)

CWE-125 — Out-of-bounds Read
CWE-908 — Use of Uninitialized Resource

References

security-advisories@github.com (x_refsource_CONFIRM, Exploit, Patch, Third Party Advisory)

Frequently asked questions

What is CVE-2026-48104?: CVE-2026-48104 is a medium-severity vulnerability in 7-zip, classified under Out-of-bounds Read. CVSS score: 4.2/10. Published 2026-06-05.
How severe is CVE-2026-48104?: Medium severity. CVSS v3 base score is 4.2 out of 10.