CVE-2026-29518: fallo de gravedad alta en RsyncProject rsync
Rsync < 3.4.3 TOCTOU Race Condition Allows Symlink-Based Arbitrary File Write
Publicada el · Actualizada el
Aviso por correo cuando entre en el KEV, tenga PoC pública o suba de nota.
21Vexday Risk Score
Sin señal de explotación. Ningún artefacto público de explotación conocido hasta ahora.
ssvc Trackcvss 7.3epss 0.2%
Rsync versions before 3.4.3 contain a time-of-check to time-of-use (TOCTOU) race condition in daemon file handling that allows attackers to redirect file writes outside intended directories by replacing parent directory components with symbolic links. Attackers with write access to a module path can exploit this race condition to create or overwrite arbitrary files, potentially modifying sensitive system files and achieving privilege escalation when the daemon runs with elevated privileges. This vulnerability can only be triggered if the chroot setting is false.
CVSS:4.0/AV:L/AC:H/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Productos afectados
RsyncProject · rsyncCVEs relacionadas — RsyncProject rsync
En el mismo producto, de las más peligrosas a las menos.
CVE-2026-43618MEDIUMRsync < 3.4.3 Integer Overflow Information DisclosureEPSS 0.8%CVE-2026-70459MEDIUMrsync 3.0.0 < 3.5.0 Daemon Crash via Malformed File List EntryEPSS 0.7%CVE-2026-70464HIGHrsync 2.0.0 < 3.5.0 Connection Slot Exhaustion DoS via Handshake StallEPSS 0.6%CVE-2026-53790CRITICALrsync < 3.5.0 Command Injection via Multiple Code PathsEPSS 0.6%CVE-2026-119741HIGHrsync < 3.5.2 Denial of Service via hash_search() Checksum CollisionsEPSS 0.6%CVE-2026-70453HIGHrsync < 3.5.0 Algorithmic Complexity DoS via hash_search()EPSS 0.6%
Referencias
https://access.redhat.com/errata/RHSA-2026:26332https://access.redhat.com/errata/RHSA-2026:26408https://access.redhat.com/errata/RHSA-2026:26410https://access.redhat.com/errata/RHSA-2026:29197https://access.redhat.com/errata/RHSA-2026:54769https://access.redhat.com/security/cve/CVE-2026-29518https://bugzilla.redhat.com/show_bug.cgi?id=2469055https://github.com/RsyncProject/rsync/pull/895/changes/8471fdd1561049ef5f58df44a1811a50bd9a531dhttps://github.com/RsyncProject/rsync/releases/tag/v3.4.3https://michael.stapelberg.ch/posts/2026-05-24-minimal-memory-safe-go-rsync-vulns/https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-29518.jsonhttps://www.vulncheck.com/advisories/rsync-toctou-race-condition-allows-symlink-based-arbitrary-file-write