FreeBSD/OpenBSD/MacOS X realpath memory corruption

CVSS Meta Temp Score
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CTI Interest Score
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6.6$0-$5k0.00

Summaryinfo

A vulnerability categorized as very critical has been discovered in FreeBSD, OpenBSD and MacOS X. This impacts the function realpath. Such manipulation leads to memory corruption. This vulnerability is listed as CVE-2003-0466. The attack may be performed from remote. In addition, an exploit is available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as very critical, has been found in FreeBSD, OpenBSD and MacOS X (Operating System) (affected version unknown). Affected by this issue is the function realpath. The manipulation with an unknown input leads to a memory corruption vulnerability. Using CWE to declare the problem leads to CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. Impacted is confidentiality, integrity, and availability. CVE summarizes:

Off-by-one error in the fb_realpath() function, as derived from the realpath function in BSD, may allow attackers to execute arbitrary code, as demonstrated in wu-ftpd 2.5.0 through 2.6.2 via commands that cause pathnames of length MAXPATHLEN+1 to trigger a buffer overflow, including (1) STOR, (2) RETR, (3) APPE, (4) DELE, (5) MKD, (6) RMD, (7) STOU, or (8) RNTO.

The weakness was presented 08/04/2003 by Janusz Niewiadomski and Wojciech Purczynski with iSEC Security Research (Website). The advisory is available at ftp.freebsd.org. This vulnerability is handled as CVE-2003-0466 since 06/26/2003. The attack may be launched remotely. No form of authentication is required for exploitation. Technical details as well as a public exploit are known. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 08/13/2025).

After immediately, there has been an exploit disclosed. The exploit is available at securiteam.com. It is declared as proof-of-concept. As 0-day the estimated underground price was around $25k-$100k. The vulnerability scanner Nessus provides a plugin with the ID 16907 (HP-UX PHNE_29462 : s700_800 11.22 ftpd(1M) and ftp(1) patch), which helps to determine the existence of the flaw in a target environment. It is assigned to the family HP-UX Local Security Checks and running in the context r. The commercial vulnerability scanner Qualys is able to test this issue with plugin 27200 (WU-FTPD FB_RealPath Off-By-One Buffer Overflow Vulnerability).

Upgrading eliminates this vulnerability. A possible mitigation has been published even before and not after the disclosure of the vulnerability. Attack attempts may be identified with Snort ID 2392. In this case the pattern RETR is used for detection. Furthermore it is possible to detect and prevent this kind of attack with TippingPoint and the filter 2314.

The vulnerability is also documented in the databases at X-Force (12785), Exploit-DB (74), Tenable (16907), SecurityFocus (BID 8315†) and OSVDB (2133†). securiteam.com is providing further details. See VDB-217, VDB-298 and VDB-82042 for similar entries. If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.3
VulDB Meta Temp Score: 6.6

VulDB Base Score: 7.3
VulDB Temp Score: 6.6
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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Exploitinginfo

Class: Memory corruption
CWE: CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Access: Public
Status: Proof-of-Concept
Download: 🔍

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EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 16907
Nessus Name: HP-UX PHNE_29462 : s700_800 11.22 ftpd(1M) and ftp(1) patch
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍
Nessus Port: 🔍

OpenVAS ID: 53646
OpenVAS Name: Debian Security Advisory DSA 357-1 (wu-ftpd)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Exploit-DB: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
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Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍
Exploit Delay Time: 🔍
Snort ID: 2392
Snort Message: FTP RETR overflow attempt
Snort Class: 🔍
Snort Pattern: 🔍

Suricata ID: 2102391
Suricata Class: 🔍
Suricata Message: 🔍

TippingPoint: 🔍

McAfee IPS: 🔍
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SourceFire IPS: 🔍
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Timelineinfo

06/26/2003 🔍
07/31/2003 +35 days 🔍
07/31/2003 +0 days 🔍
08/04/2003 +4 days 🔍
08/04/2003 +0 days 🔍
08/04/2003 +0 days 🔍
08/05/2003 +1 days 🔍
08/13/2003 +8 days 🔍
08/14/2003 +0 days 🔍
08/27/2003 +13 days 🔍
02/16/2005 +539 days 🔍
08/13/2025 +7483 days 🔍

Sourcesinfo

Product: freebsd.org

Advisory: ftp.freebsd.org
Researcher: Janusz Niewiadomski, Wojciech Purczynski
Organization: iSEC Security Research
Status: Confirmed

CVE: CVE-2003-0466 (🔍)
GCVE (CVE): GCVE-0-2003-0466
GCVE (VulDB): GCVE-100-218

OVAL: 🔍

CERT: 🔍
X-Force: 12785 - libc realpath(3) function off-by-one buffer overflow, High Risk
SecurityFocus: 8315
Secunia: 9535 - Mac OS X "fb_realpath()" Buffer Overflow Vulnerability, Highly Critical
OSVDB: 2133 - WU-FTPD fb_realpath() Function Off-by-one Error
SecurityTracker: 1007380 - (FreeBSD Issues Fix) 'libc' Off-by-One Overflow in realpath() May Let Remote Users Execute Arbitrary Code
SecuriTeam: securiteam.com
Vulnerability Center: 1678 - BSD Off-by-One Error in realpath(3) Function Allows Arbitrary Code Execution, High

scip Labs: https://www.scip.ch/en/?labs.20180712
Misc.: 🔍
See also: 🔍

Entryinfo

Created: 08/05/2003 12:06
Updated: 08/13/2025 15:46
Changes: 08/05/2003 12:06 (106), 12/13/2016 20:21 (5), 03/08/2021 15:47 (3), 08/31/2024 08:22 (14), 12/26/2024 13:13 (1), 08/13/2025 15:46 (2)
Complete: 🔍
Cache ID: 216:3A9:103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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