VulnerabilityPublished 13 Aug 2026Updated 14 Aug 2026

CVE-2026-53798: RsyncProject rsync · Incorrect Type Conversion or Cast

Affects RsyncProject rsyncSource CVE Database V5

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Not known to be exploited · CVSS 6.9 Medium · fixed in 3.5.0 : update RsyncProject rsync when convenient.

Data as of 12 Nov 2026, 23:24 UTC

CVSS 4.0 base score

6.9Medium

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.4% chance of exploitation in 30 days – higher than 37% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 3.5.0

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N

Attack Vector: Network
Attack Complexity: Low
Attack Requirements: None
Privileges Required: None
User Interaction: None
Vulnerable system confidentiality: None
Vulnerable system integrity: Low
Vulnerable system availability: None
Subsequent system confidentiality: None
Subsequent system integrity: None
Subsequent system availability: None

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable system is bound to the network stack and the set of possible attackers extends beyond the other options listed below, up to and including the entire Internet. Such a vulnerability is often termed “remotely exploitable” and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: The attacker must take no measurable action to exploit the vulnerability. The attack requires no target-specific circumvention to exploit the vulnerability. An attacker can expect repeatable success against the vulnerable system.
Attack Requirements: None: The successful attack does not depend on the deployment and execution conditions of the vulnerable system. The attacker can expect to be able to reach the vulnerability and execute the exploit under all or most instances of the vulnerability.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files of the vulnerable system to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without interaction from any human user, other than the attacker.
Vulnerable system confidentiality: None: There is no loss of confidentiality within the Vulnerable System.
Vulnerable system integrity: Low: Modification of data is possible, but the attacker does not have control over the consequence of a modification, or the amount of modification is limited. The data modification does not have a direct, serious impact to the Vulnerable System.
Vulnerable system availability: None: There is no impact to availability within the Vulnerable System.
Subsequent system confidentiality: None: There is no loss of confidentiality within the Subsequent System or all confidentiality impact is constrained to the Vulnerable System.
Subsequent system integrity: None: There is no loss of integrity within the Subsequent System or all integrity impact is constrained to the Vulnerable System.
Subsequent system availability: None: There is no impact to availability within the Subsequent System or all availability impact is constrained to the Vulnerable System.

Definitions: FIRST CVSS v4.0 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 13 Aug 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 13 Nov 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponized: A Metasploit exploit module or Exploit-DB entry exists (Metasploit scanner modules do not count), or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Affected software

Product	Affected	Fixed in
RsyncProjectrsync	Affected <=3.4.4	Fixed in–
GitHubrsync`pkg:github/rsync`Other threats	Affected <=3.4.4	Fixed in–

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

A fix is available in rsync version 3.5.0 and later. Users should upgrade to version 3.5.0 or newer to remediate this vulnerability. Until then, restricting local access to trusted users can reduce risk. Patch status is confirmed by the versioning information indicating affected versions are up to 3.4.4, with 3.5.0 as the fixed version.

Description

CVE-2026-53798 is a privilege confusion vulnerability in rsync versions up to 3.4.4. It arises from incorrect handling of uid/gid lookups in the name-converter subprocess, where empty responses are misinterpreted as root (uid/gid 0). This flaw allows local attackers to cause transferred files to be owned by root by manipulating the name-converter responses. The vulnerability has a medium severity with a CVSS score of 6.9.

Impact

Local attackers can exploit this vulnerability to cause files transferred by rsync to be owned by root, potentially leading to unauthorized privilege escalation or improper file ownership. This could affect system integrity and security by granting elevated privileges to files that should not have them.

Summary

The vulnerability in rsync before version 3.5.0 involves the name-converter subprocess used for uid/gid mapping. When this subprocess returns an empty response for a uid or gid lookup, rsync incorrectly treats it as a successful resolution to uid/gid 0 (root) instead of a failure. If the name-converter also signals fake super-user status, rsync assigns root ownership to transferred files. This is a privilege confusion issue categorized under CWE-704 (Incorrect Type Conversion or Cast).

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 18 Oct 2026, 00:50 UTC

WeaknessesCWE-704

Technical details

References

Community reviews

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