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CVE-2026-53794 (GCVE-0-2026-53794)

Vulnerability from cvelistv5 – Published: 2026-08-13 14:39 – Updated: 2026-08-14 16:50
VLAI
Title
rsync < 3.5.0 Denial of Service via --max-alloc=0 Logic Error
Summary
rsync before 3.5.0 contains a logic error in --max-alloc handling that allows a sender or configuration setting --max-alloc=0 to disable allocation sanity checks entirely rather than enforcing a zero-byte cap. Attackers can exploit this flaw to cause the receiver to attempt unbounded memory allocations for file list and data structures, potentially exhausting available memory and causing a denial of service.
Severity
6.9 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-13 15:34 UTC
CWE
  • CWE-1284 - Improper Validation of Specified Quantity in Input
Assigner
References
Impacted products
Vendor Product Version CPE status
RsyncProject rsync Affected: 0 , ≤ 3.4.4 (semver)
Unaffected: 3.5.0 (semver)
    cpe:2.3:a:samba:rsync:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-08-12 00:00
Credits
azqzazq1
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

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.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • 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.


Detection rules are retrieved from Rulezet.


Related by attack behaviour

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.