CVE-2026-55195 | BDVDB-2026-346246 Detail

miurahrpy7zr

Description#

py7zr is a Python-based library and utility to support 7zip archive compression, decompression, encryption and decryption. Prior to 1.1.3, py7zr's Worker.decompress() extracted archive entries without tracking total decompressed size, allowing a crafted .7z file such as a 15.6 KB archive that expands to 100 MB to exhaust disk or memory before extraction completes. This issue is fixed in version 1.1.3.

Impact#

Per CVSS v4.0: confidentiality impact none, integrity impact none, availability impact high. Attack vector: network.

Weaknesses#

CWE-409 Improper Handling of Highly Compressed Data (Data Amplification)

References#

Exploit#

No public exploit known

History#

Version 12026-07-08Record published in the CVE List.
Version 22026-07-09Most recent update recorded in the CVE List.

Published

Published: 2026-07-08
Last modified: 2026-07-09

Vendor information

Vendor: miurahr
Product: py7zr

All miurahr vulnerabilities

Score

8.7 High

EPSS

less than 1%, Very Low

Estimated chance of exploitation in the next 30 days. EPSS percentile: 25.3.

KEV

Not listed in the CISA Known Exploited Vulnerabilities catalog.

Impact

Not classified

Action

No specific action is recorded in the source data. Check the references for vendor guidance.

Affected Systems

Vulnerable
< 1.1.3
Fixed
Not stated

Scoring System

CVSS v4.0

8.7 High

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Metric breakdown
Attack Vector	Network
Attack Complexity	Low
Attack Requirements	None
Privileges Required	None
User Interaction	None
Vulnerable System Confidentiality	None
Vulnerable System Integrity	None
Vulnerable System Availability	High
Subsequent System Confidentiality	None
Subsequent System Integrity	None
Subsequent System Availability	None

CVSS v3.1

Not available

CVSS v3.0

Not available

CVSS v2

Not available

Source: CVE List v5 (record); CISA KEV (kev, action); FIRST EPSS (epss).