9.8

CVE-2023-53959: FileZilla Client 3.63.1 DLL Hijacking via Missing TextShaping.dll

Analyzed
AliasesUBUNTU-CVE-2023-53959
Published 19-12-2025Last modified 07-04-2026

Vulnerability summary

CVE-2023-53959 is a critical (CVSS 9.8) Uncontrolled Search Path Element vulnerability in filezilla-project filezilla_client. EPSS estimates a 0.85% chance of exploitation in the next 30 days, higher than 58.3% of scored vulnerabilities. 1 public exploit is recorded.

Priority
Prioritisepublic exploit

Public exploit (exploit-database, 06-04-2023)

Source freshness unavailable

How is this decided?
CVSS score
9.8/10
010
Critical · v3.1 (CVE.org)
EPSS score
0.85%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits1exploit-database

Timeline

  1. 19-12-2025
    PublishedVulnerability first disclosed.
  2. 07-04-2026
    Last modifiedVulnerability information updated.

Description

FileZilla Client 3.63.1 contains a DLL hijacking vulnerability that allows attackers to execute malicious code by placing a crafted TextShaping.dll in the application directory. Attackers can generate a reverse shell payload using msfvenom and replace the missing DLL to achieve remote code execution when the application launches.

CVSS metrics

6 scores · 3 sources · 2 versions

EPSS trend

Probability

0.85%

Chance of exploitation in the next 30 days

Percentile

58%

Versus all other CVEs

30-day change

No change 0.00 pp

From 0.85% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

1 found
  • exploit-databaselocalwindowsUnverified

    FileZilla Client 3.63.1 - 'TextShaping.dl' DLL Hijacking

    Maturity: poc

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: local access, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.

Filezilla-project1 product
Ubuntu1 product
  • filezillaAll versions (No fix recorded)

2 vendors · 2 products

References

5 links