CVE-2026-85091
High
Description
zlib versions 1.3.1.2 through 1.3.2 contain a heap buffer overflow vulnerability in the gz_vacate() function when processing non-blocking gzwrite() operations with stale external buffer pointers. Attackers can trigger the overflow by calling gzprintf() or gzvprintf() after a write stall, causing an unchecked memmove() to write beyond the internal input buffer boundary.
SeverityHigh
CVSS7.4
Exploit probability—
Product
Microsoft Azl3 Kata-containers
PublishedSep 3, 2026
First seenSep 3, 2026
Weakness typeCWE-787Out-of-bounds write
How to fix
Sources list no fixed version or patch link for this vulnerability.
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| microsoft azl3_kata-containers_4.1.0.kata0-1 | No range specified | — |
| microsoft azl3_zlib_1.3.2-1 | No range specified | — |
| microsoft azl3_cloud-hypervisor_52.0.152-1 | No range specified | — |
| microsoft azl3_kata-containers_3.32.0.kata0-2 | No range specified | — |
| microsoft azl3_kata-containers_3.32.0.kata0-5 | No range specified | — |
| microsoft azl3_zlib_1.3.2-2 | No range specified | — |
| microsoft azl3_kata-containers_4.1.0.kata1-2 | No range specified | — |
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