CVE-2026-27820
Buffer Overflow in Zlib::GzipReader ungetc via large input leads to memory corruption
9.8
CRITICAL
CVSS 3.1
EPSS 0.56%
描述
zlib is a Ruby interface for the zlib compression/decompression library. Versions 3.0.0 and below, 3.1.0, 3.1.1, 3.2.0 and 3.2.1 contain a buffer overflow vulnerability in the Zlib::GzipReader. The zstream_buffer_ungets function prepends caller-provided bytes ahead of previously produced output but fails to guarantee the backing Ruby string has enough capacity before the memmove shifts the existing data. This can lead to memory corruption when the buffer length exceeds capacity. This issue has been fixed in versions 3.0.1, 3.1.2 and 3.2.3.
如何修補 CVE-2026-27820
要修補 CVE-2026-27820,請將受影響套件升級到下列已修補版本。
- —升級至 3.4.9-r0 或更新版本
- —未列出修補版本
- —未列出修補版本
- —未列出修補版本
- —升級至 3.2.3 或更新版本
CVE-2026-27820 正在被利用嗎?
低 — EPSS 為 0.6%,目前沒有觀察到大規模利用活動。
受影響套件(5)
- from 0, < 3.4.9-r0
- from 0
- from 0
- from 0
- >= 3.2.0, < 3.2.3
CVSS 分數
| 來源 | 版本 | 嚴重程度 | 向量 |
|---|---|---|---|
| osv | CVSS 4.0 | — | CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U |
| osv | CVSS 3.1 | CRITICAL9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |