CVE-2026-70457

rsync 3.2.3 before 3.5.0 contains an out-of-bounds write in parse_size_arg() where the return value of snprintf() is used directly as an index into a .bss-segment array without bounds checking. When snprintf truncates the formatted size string, the return value equals the number of characters that would have been written including the truncated portion, and this value may exceed the array length. The subsequent indexed write targets memory outside the intended array bounds, corrupting .bss memory.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 4.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/RsyncProject/rsync/releases/tag/v3.5.0	Product Release Notes
https://github.com/RsyncProject/rsync/security/advisories/GHSA-pg7g-xqmr-xpfh	Vendor Advisory
https://www.vulncheck.com/advisories/rsync-out-of-bounds-write-via-parse-size-arg	Release Notes Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:samba:rsync:*:*:*:*:*:*:*:*

History

23 Oct 2026, 18:10

Type	Values Removed	Values Added
Summary		(es) rsync 3.2.3 anterior a 3.5.0 contiene una escritura fuera de límites en parse_size_arg() donde el valor de retorno de snprintf() se utiliza directamente como un índice en un array del segmento .bss sin comprobación de límites. Cuando snprintf trunca la cadena de tamaño formateada, el valor de retorno es igual al número de caracteres que se habrían escrito incluyendo la porción truncada, y este valor puede exceder la longitud del array. La escritura indexada subsiguiente apunta a memoria fuera de los límites previstos del array, corrompiendo la memoria .bss.

Information

Published : 2026-08-13 15:19

Updated : 2026-10-24 16:10

NVD link : CVE-2026-70457

Mitre link : CVE-2026-70457

CVE.ORG link : CVE-2026-70457

JSON object : View

Products Affected

samba

rsync

CWE

CWE-131

Incorrect Calculation of Buffer Size

CWE-787

Out-of-bounds Write

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