← Vulnerability feed

Vulnerability record · CVE-2026-70457 · published 13 August 2026

CVE-2026-70457: Samba rsync out-of-bounds write vulnerability

Samba · Rsync

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.

8.3 CVSS 4.0 High EPSS 0.52% · top 58.0% CWE-131 · CWE-131CWE-787 · Out-of-bounds write
8.3CVSS 4.0 base score
0.52%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
3References
31 Aug 2026Last modified by NVD

Description

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:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://github.com/RsyncProject/rsync/releases/tag/v3.5.0 ProductRelease 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 NotesThird Party Advisory

Track CVE-2026-70457 inside VULONE

Watch it alongside the ransomware crews, C2 infrastructure and forum chatter that reference it, query it through the API and pull it into your SIEM over TAXII.

Start free Open in platform

Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

9.8CVE-2024-12084rsync daemon heap buffer overflow via attacker-controlled checksum lengthThe rsync daemon mishandles attacker-controlled checksum lengths (s2length), allowing an out-of-bounds write in the sum2 buffer when MAX_DIGEST_LEN e…EPSS 72%analysed9.8CVE-2017-17434Samba rsync vulnerabilityThe daemon in rsync 3.1.2, and 3.1.3-development before 2017-12-03, does not check for fnamecmp filenames in the daemon_filter_list data structure (i…EPSS 3.3%9.8CVE-2017-16548Samba rsync out-of-bounds read vulnerabilityThe receive_xattr function in xattrs.c in rsync 3.1.2 and 3.1.3-development does not check for a trailing '\0' character in an xattr name, which allo…EPSS 5.8%9.8CVE-2017-15994Samba rsync vulnerabilityrsync 3.1.3-development before 2017-10-24 mishandles archaic checksums, which makes it easier for remote attackers to bypass intended access restrict…EPSS 1.0%9.1CVE-2026-53791Samba rsync authentication bypass by spoofing vulnerabilityrsync daemon before 3.5.0 contains an IP address spoofing vulnerability that allows unauthenticated remote attackers to bypass IP-based access contro…EPSS 0.71%8.8CVE-2026-70461Samba rsync out-of-bounds write vulnerabilityrsync 3.2.5 before 3.5.0 contains a heap out-of-bounds write vulnerability that allows remote unauthenticated attackers to write one attacker-control…EPSS 0.79%8.7CVE-2026-70455Samba rsync allocation without limits vulnerabilityrsync 3.4.2 before 3.5.0 contains a denial of service vulnerability that allows a remote sender to exhaust system resources by specifying the --zt sh…EPSS 0.78%8.6CVE-2026-70463Samba rsync incorrect authorization vulnerabilityrsync 3.1.0 before 3.5.0 contains an authorization bypass in auth users directive parsing. The auth users parser uses comma-only tokenization when sp…EPSS 0.47%

Source: NIST National Vulnerability Database (record CVE-2026-70457), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.