CVE-2026-43618 (GCVE-0-2026-43618)

Vulnerability from cvelistv5 – Published: 2026-05-20 00:50 – Updated: 2026-05-20 13:04
VLAI?
Title
Rsync < 3.4.3 Integer Overflow Information Disclosure
Summary
Rsync version 3.4.2 and prior contain an integer overflow vulnerability in the compressed-token decoder where a 32-bit signed counter is not checked for overflow, allowing a malicious sender to trigger an overflow that causes the receiver process to read and return data from outside the intended buffer bounds. Attackers can exploit this vulnerability to disclose process memory contents including environment variables, passwords, heap and stack data, and library memory pointers, significantly reducing ASLR effectiveness and facilitating further exploitation.
Severity ?
6.1 (Medium)
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:H/SC:N/SI:N/SA:N
8.1 (High)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
CWE
  • CWE-190 - Integer Overflow or Wraparound
  • CWE-125 - Out-of-bounds Read
Assigner
References
Impacted products
Vendor Product Version
RsyncProject rsync Affected: 0 , < 3.4.3 (semver)
Create a notification for this product.
Date Public ?
2026-05-19 00:00
Credits
Omar Elsayed (@seks99x)
Show details on NVD website
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Taxonomy of the tags.




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.