CVE-2021-32825

Name: CVE-2021-32825
Creator: NVD / NIST
Published: 2021-08-16T19:15:14.207+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9.1/10EPSS 0.92%

Last modified Jun 17, 2026

CVE-2021-32825 is a critical-severity vulnerability rated 9.1/10 on the CVSS scale. bblfshd is an open source self-hosted server for source code parsing. In bblfshd before commit 4265465b9b6fb5663c30ee43806126012066aad4 there is a "zipslip" vulnerability. EPSS estimates a 0.92% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1

9.1/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

EPSS Probability

0.92%

55.6th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Bblfshd Project	Bblfshd	< 2021-08-11

References

https://github.com/bblfsh/bblfshd/commit/4265465b9b6fb5663c30ee43806126012066aad4Patch, Third Party Advisory
https://github.com/bblfsh/bblfshd/pull/341Patch, Third Party Advisory
https://securitylab.github.com/advisories/GHSL-2020-258-zipslip-bblfshd/Exploit, Third Party Advisory
https://github.com/bblfsh/bblfshd/commit/4265465b9b6fb5663c30ee43806126012066aad4Patch, Third Party Advisory
https://github.com/bblfsh/bblfshd/pull/341Patch, Third Party Advisory
https://securitylab.github.com/advisories/GHSL-2020-258-zipslip-bblfshd/Exploit, Third Party Advisory

Timeline

Published: Aug 16, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-32825?

How severe is CVE-2021-32825?

CVE-2021-32825 has a CVSS score of 9.1/10 (CRITICAL severity). The EPSS model estimates a 0.92% probability of exploitation in the next 30 days.

How do I fix CVE-2021-32825?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-32825?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST