Exim up to 4.99.4 queue-name path traversal

CVSS Meta Temp Score
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Current Exploit Price (≈)
Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.
CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
9.5$0-$5k2.63+

Summaryinfo

A vulnerability classified as very critical was found in Exim up to 4.99.4. This vulnerability affects unknown code. Executing a manipulation of the argument queue-name can lead to path traversal. This vulnerability appears as CVE-2026-66140. The attack may be performed from remote. There is no available exploit.

Detailsinfo

A vulnerability was found in Exim up to 4.99.4. It has been declared as very critical. This vulnerability affects an unknown function. The manipulation of the argument queue-name with an unknown input leads to a path traversal vulnerability. The CWE definition for the vulnerability is CWE-22. The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

Exim before 4.99.5 allows directory traversal to access files outside of the spool area, and consequently gain privileges, because arguments related to queue-name are mishandled.

The advisory is available at openwall.com. This vulnerability was named CVE-2026-66140 since 07/24/2026. The exploitation appears to be easy. The attack can be initiated remotely. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 07/24/2026). This vulnerability is assigned to T1006 by the MITRE ATT&CK project.

Upgrading to version 4.99.5 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-48478). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 9.9
VulDB Meta Temp Score: 9.5

VulDB Base Score: 9.9
VulDB Temp Score: 9.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Path traversal
CWE: CWE-22
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Exim 4.99.5

Timelineinfo

07/24/2026 Advisory disclosed
07/24/2026 +0 days CVE reserved
07/24/2026 +0 days VulDB entry created
07/24/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: openwall.com
Status: Confirmed

CVE: CVE-2026-66140 (🔒)
GCVE (CVE): GCVE-0-2026-66140
GCVE (VulDB): GCVE-100-382858
EUVD: 🔒

Entryinfo

Created: 07/24/2026 06:57
Updated: 07/24/2026 08:19
Changes: 07/24/2026 06:57 (54), 07/24/2026 08:19 (1)
Complete: 🔍
Cache ID: 216::103

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

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