CVE-2021-32825

ZipSlip vulnerability in bblfshd

CRITICAL
9.1
CVSS Score
Published: August 16, 2021 at 07:00 PM UTC
Updated: June 17, 2026 at 03:53 AM UTC
2 products affected across 2 vendorsBblfshdProject Bblfshd

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Severity
CRITICAL9.1
Exploit prediction
EPSS 0.9%

Description

bblfshd is an open source self-hosted server for source code parsing. In bblfshd before commit 4265465b9b6fb5663c30ee43806126012066aad4 there is a "zipslip" vulnerability. The unsafe handling of symbolic links in an unpacking routine may enable attackers to read and/or write to arbitrary locations outside the designated target folder. This issue may lead to arbitrary file write (with same permissions as the program running the unpack operation) if the attacker can control the archive file. Additionally, if the attacker has read access to the unpacked files, he may be able to read arbitrary system files the parent process has permissions to read. For more details including a PoC see the referenced GHSL-2020-258.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 2021-08-11
Affected range stops below 2021-08-11, so it looks safe — our inference, not a vendor statement
v < 4265465b9b6fb5663c30ee43806126012066aad4

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (3)

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
NONE
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-23CWE-59

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