Exim libspf2 integer underflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.8$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as critical, was found in Exim libspf2. This impacts an unknown function. Such manipulation leads to integer underflow. This vulnerability is listed as CVE-2023-42118. The attack must be carried out from within the local network. There is no available exploit.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Exim libspf2 (Mail Server Software) (affected version not known). Affected by this issue is some unknown functionality. The manipulation with an unknown input leads to a integer underflow vulnerability. Using CWE to declare the problem leads to CWE-191. The product subtracts one value from another, such that the result is less than the minimum allowable integer value, which produces a value that is not equal to the correct result. Impacted is confidentiality, integrity, and availability. CVE summarizes:

Exim libspf2 Integer Underflow Remote Code Execution Vulnerability. This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of Exim libspf2. Authentication is not required to exploit this vulnerability. The specific flaw exists within the parsing of SPF macros. When parsing SPF macros, the process does not properly validate user-supplied data, which can result in an integer underflow before writing to memory. An attacker can leverage this vulnerability to execute code in the context of the service account. . Was ZDI-CAN-17578.

The weakness was presented 09/28/2023 as ZDI-23-1472. The advisory is shared for download at zerodayinitiative.com. This vulnerability is handled as CVE-2023-42118 since 09/06/2023. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 08/08/2025).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

Vendor

Name

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.9
VulDB Meta Temp Score: 7.8

VulDB Base Score: 7.5
VulDB Temp Score: 7.2
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 8.8
NVD Vector: 🔍

CNA Base Score: 7.5
CNA Vector: 🔍

CVSSv2info

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

Exploitinginfo

Class: Integer underflow
CWE: CWE-191 / CWE-189
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Partially

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Timelineinfo

09/06/2023 🔍
09/28/2023 +22 days 🔍
09/28/2023 +0 days 🔍
08/08/2025 +679 days 🔍

Sourcesinfo

Advisory: ZDI-23-1472
Status: Not defined

CVE: CVE-2023-42118 (🔍)
GCVE (CVE): GCVE-0-2023-42118
GCVE (VulDB): GCVE-100-240788

Entryinfo

Created: 09/28/2023 07:49
Updated: 08/08/2025 00:30
Changes: 09/28/2023 07:49 (36), 09/19/2024 11:45 (27), 08/08/2025 00:30 (11)
Complete: 🔍
Cache ID: 216::103

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