CVE-2026-53796: rsyncproject rsync Link Following
Vulnerability summary
CVE-2026-53796 is a medium (CVSS 6.3) Link Following vulnerability in rsyncproject rsync. EPSS estimates a 0.13% chance of exploitation in the next 30 days, higher than 2.5% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 9 · Related 8Timeline
- 13-08-2026PublishedVulnerability first disclosed.
- 14-08-2026Last modifiedVulnerability information updated.
Description
rsync before 3.5.0 contains a time-of-check to time-of-use (TOCTOU) race condition vulnerability in the non-daemon receiver's destination directory handling that allows an attacker who can manipulate destination path parent components to redirect file writes to unintended locations. Attackers can substitute a symlink for a component of the destination path between the path resolution and chdir() call, causing the receiver's working directory to be established outside the intended destination tree so that subsequent relative-path file writes land in unintended filesystem locations.
CVSS metrics
8 scores · 5 sources · 2 versions- OSV · AlpineEcosystem advisory · calculated5.8MediumCVSS:4.0/AV:L/AC:H/AT:N/PR:L/UI:N/VC:N/VI:H/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:X/V:X/RE:X/U:X
- OSV · UbuntuEcosystem advisory · calculated5.8MediumCVSS:4.0/AV:L/AC:H/AT:N/PR:L/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N
- OSV · DebianEcosystem advisory · calculated5.8MediumCVSS:4.0/AV:L/AC:H/AT:N/PR:L/UI:N/VC:N/VI:H/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:X/V:X/RE:X/U:X
- NVDNIST5.8MediumCVSS:4.0/AV:L/AC:H/AT:N/PR:L/UI:N/VC:N/VI:H/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:X/V:X/RE:X/U:X
- OSV · UbuntuEcosystem advisory · calculated6.3MediumCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:H
- NVDNIST6.3MediumCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:H
EPSS trend
Probability
0.13%
Chance of exploitation in the next 30 days
Percentile
3%
Versus all other CVEs
30-day change
0.00 pp
From 0.13% on 20-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root cause- CWE-59Improper Link Resolution Before File Access ('Link Following')The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource.
- CWE-367Time-of-check Time-of-use (TOCTOU) Race ConditionThe product checks the state of a resource before using that resource, but the resource's state can change between the check and the use in a way that invalidates the results of the check.
Affected systems
Alpine1 product
- rsync< 3.5.0-r0
Debian1 product
- rsyncAll versions (No fix recorded) | < 3.5.0+ds1-0+deb13u1 | < 3.5.0+ds1-1
Rsyncproject1 product
- rsync≤ 3.4.4
Ubuntu1 product
- rsyncAll versions (No fix recorded)
4 vendors · 4 products
References
9 links- github.com/RsyncProject/rsync/releases/tag/v3.5.0Release Notes