CVE-2026-48840 - Vulnerability Details - OpenCVE

Exim 4.88 before 4.99.4, in some proxy configurations, mishandles certain short payloads, leading to disclosure of uninitialized stack memory values to a client.

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact Low

Integrity Impact None

Availability Impact None

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploitation none

Automatable yes

Technical Impact partial

Vendors	Products
Exim	Exim

Configuration 1 [-]

cpe:2.3:a:exim:exim:*:*:*:*:*:*:*:*

No data.

References

Link	Providers
http://www.openwall.com/lists/oss-security/2026/05/29/3
https://exim.org/static/doc/security/EXIM-Security-2026-05-19.1
https://www.openwall.com/lists/oss-security/2026/05/29/3

History

Mon, 01 Jun 2026 13:15:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Sat, 30 May 2026 04:30:00 +0000

Type	Values Removed	Values Added
References		http://www.openwall.com/lists/oss-security/2026/05/29/3

Sat, 30 May 2026 03:45:00 +0000

Type	Values Removed	Values Added
Title		Exim Proxy Misconfiguration Causes Uninitialized Memory Disclosure

Sat, 30 May 2026 02:15:00 +0000

Type	Values Removed	Values Added
Description		Exim 4.88 before 4.99.4, in some proxy configurations, mishandles certain short payloads, leading to disclosure of uninitialized stack memory values to a client.
First Time appeared		Exim Exim exim
Weaknesses		CWE-839
CPEs		cpe:2.3:a:exim:exim::::::::
Vendors & Products		Exim Exim exim
References		https://exim.org/static/doc/security/EXIM-Security-2026-05-19.1 https://www.openwall.com/lists/oss-security/2026/05/29/3
Metrics		cvssV3_1 `{'score': 5.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N'}`

MITRE

Status: PUBLISHED

Assigner: mitre

Published: 2026-05-30T01:50:42.637Z

Updated: 2026-06-01T12:51:18.705Z

Reserved: 2026-05-25T17:51:46.146Z

Link: CVE-2026-48840

Vulnrichment

Updated: 2026-05-30T03:08:42.289Z

NVD

Status : Analyzed

Published: 2026-05-30T02:16:19.790

Modified: 2026-06-03T19:21:38.827

Link: CVE-2026-48840

Redhat

No data.

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