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CVE-2026-48840 (GCVE-0-2026-48840)

Vulnerability from cvelistv5 – Published: 2026-05-30 01:50 – Updated: 2026-06-05 09:07 X_Open Source
VLAI
Summary
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.
Severity
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-01 12:51 UTC
CWE
  • CWE-839 - Numeric Range Comparison Without Minimum Check
Assigner
References
Impacted products
Vendor Product Version CPE status
Exim Exim Affected: 4.88 , < 4.99.4 (custom)
    cpe:2.3:a:exim:exim:*:*:*:*:*:*:*:*
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Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.