CVE-2023-49096VulnerabilityPublished 6 Dec 2023Updated 28 May 2025

CVE-2023-49096: jellyfin · Argument Injection

Affects jellyfinSource CVE Database V5

Not known to be exploited · CVSS 7.7 High : upgrade to 10.8.13 soon.

Data as of 25 Oct 2026, 19:02 UTC

CVSS 3.1 base score

7.7High

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

EPSS: 1.2% chance of exploitation in 30 days – higher than 69% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 10.8.13

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:L

Attack Vector: Network
Attack Complexity: High
Privileges Required: None
User Interaction: None
Scope: Unchanged
Confidentiality: High
Integrity: High
Availability: Low

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

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, 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: High: A successful attack depends on conditions beyond the attacker's control. That is, a successful attack cannot be accomplished at will, but requires the attacker to invest in some measurable amount of effort in preparation or execution against the vulnerable component before a successful attack can be expected. For example, a successful attack may require an attacker to: gather knowledge about the environment in which the vulnerable target/component exists; prepare the target environment to improve exploit reliability; or inject themselves into the logical network path between the target and the resource requested by the victim in order to read and/or modify network communications (e.g., a man in the middle attack).
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: High: There is total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact.
Integrity: High: There is a total loss of integrity, or a complete loss of protection. For example, the attacker is able to modify any/all files protected by the impacted component. Alternatively, only some files can be modified, but malicious modification would present a direct, serious consequence to the impacted component.
Availability: Low: Performance is reduced or there are interruptions in resource availability. Even if repeated exploitation of the vulnerability is possible, the attacker does not have the ability to completely deny service to legitimate users. The resources in the impacted component are either partially available all of the time, or fully available only some of the time, but overall there is no direct, serious consequence to the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 6 Dec 2023
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: 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 2026-10-25.

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.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC 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

Upgrade jellyfin/jellyfin to 10.8.13.

Affected software

Product	Affected	Fixed in
GitHubjellyfin/jellyfin`pkg:github/jellyfin/jellyfin`Other threats	Affected <10.8.13	Fixed in 10.8.13

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

AI-suggested

1. Immediate upgrade of all Jellyfin instances to version 10.8.13 or later, where the vulnerability is patched, is the most effective mitigation. 2. Restrict network access to Jellyfin servers by implementing firewall rules or VPN access, limiting exposure to the internet and reducing the attack surface. 3. Monitor server logs for unusual requests to the vulnerable endpoints, especially those containing suspicious query parameters like `videoCodec` and `audioCodec`. 4. Employ application-layer filtering or web application firewalls (WAFs) to detect and block malformed or suspicious requests targeting the vulnerable endpoints. 5. Conduct regular audits of media item IDs and access patterns to detect potential reconnaissance attempts aimed at guessing valid GUIDs. 6. Isolate Jellyfin servers in segmented network zones with minimal privileges to limit potential lateral movement if compromised. 7. Educate administrators about the risks of exposing media servers publicly and encourage secure deployment practices. Since no workarounds exist, patching combined with network-level controls and monitoring is critical.

Description

Jellyfin is a Free Software Media System for managing and streaming media. In affected versions there is an argument injection in the VideosController, specifically the `/Videos/<itemId>/stream` and `/Videos/<itemId>/stream.<container>` endpoints which are present in the current Jellyfin version. Additional endpoints in the AudioController might also be vulnerable, as they differ only slightly in execution. Those endpoints are reachable by an unauthenticated user. In order to exploit this vulnerability an unauthenticated attacker has to guess an itemId, which is a completely random GUID. It’s a very unlikely case even for a large media database with lots of items. Without an additional information leak, this vulnerability shouldn’t be directly exploitable, even if the instance is reachable from the Internet. There are a lot of query parameters that get accepted by the method. At least two of those, videoCodec and audioCodec are vulnerable to the argument injection. The values can be traced through a lot of code and might be changed in the process. However, the fallback is to always use them as-is, which means we can inject our own arguments. Those arguments land in the command line of FFmpeg. Because UseShellExecute is always set to false, we can’t simply terminate the FFmpeg command and execute our own. It should only be possible to add additional arguments to FFmpeg, which is powerful enough as it stands. There is probably a way of overwriting an arbitrary file with malicious content. This vulnerability has been addressed in version 10.8.13. Users are advised to upgrade. There are no known workarounds for this vulnerability.

Impact

For European organizations using Jellyfin to manage and stream media, this vulnerability poses a significant risk. An attacker exploiting this flaw could manipulate FFmpeg processing commands to inject malicious arguments, potentially overwriting files or altering media streams. This could lead to unauthorized access to sensitive media content, data tampering, or even remote code execution if the attacker crafts payloads that exploit FFmpeg's processing capabilities. Given that Jellyfin instances are often deployed in home, educational, or small business environments, the risk extends to privacy breaches and service disruptions. Organizations with publicly accessible Jellyfin servers are particularly vulnerable, as the attack requires no authentication and can be launched remotely. The difficulty in guessing valid item IDs reduces the likelihood of widespread exploitation but does not eliminate targeted attacks, especially if attackers gain auxiliary information about media libraries. The absence of workarounds means organizations must rely on timely patching to mitigate risk. The vulnerability could also be leveraged as a foothold for lateral movement within networks if the compromised server has broader access, increasing the potential impact on organizational IT infrastructure.

Summary

CVE-2023-49096 is a high-severity vulnerability affecting Jellyfin, an open-source media server software used for managing and streaming media content. The vulnerability is classified under CWE-88, which involves improper neutralization of argument delimiters leading to command injection. Specifically, the flaw exists in the VideosController endpoints `/Videos/<itemId>/stream` and `/Videos/<itemId>/stream.<container>`, and potentially in similar AudioController endpoints. These endpoints accept various query parameters, notably `videoCodec` and `audioCodec`, which are vulnerable to argument injection. An unauthenticated attacker can exploit this by injecting additional arguments into the FFmpeg command line used by Jellyfin to process media streams. Although the `UseShellExecute` flag is set to false, preventing full command termination and arbitrary command execution, the attacker can append arguments to FFmpeg commands. This capability could allow overwriting arbitrary files with malicious content, potentially leading to remote code execution or system compromise. Exploitation requires guessing a valid `itemId`, which is a random GUID, making successful exploitation less likely without additional information leaks. The vulnerability affects all Jellyfin versions prior to 10.8.13, where it has been patched. No known workarounds exist, and the vulnerability is exploitable remotely without authentication but with high attack complexity due to the need to guess valid item IDs. The CVSS v3.1 base score is 7.7, reflecting high impact on confidentiality and integrity, with low impact on availability.

CWE-88Improper Neutralization of Argument Delimiters in a Command ('Argument Injection') (opens in a new tab)
Base weaknessOWASP Top 10 A05:2025: Injection (opens in a new tab)
The product constructs a string for a command to be executed by a separate component in another control sphere, but it does not properly delimit the intended arguments, options, or switches within that command string.
Implementation · Parameterization
Where possible, avoid building a single string that contains the command and its arguments. Some languages or frameworks have functions that support specifying independent arguments, e.g. as an array, which is used to automatically perform the appropriate quoting or escaping while building the command.
Architecture and Design · Input Validation
Understand all the potential areas where untrusted inputs can enter your product: parameters or arguments, cookies, anything read from the network, environment variables, request headers as well as content, URL components, e-mail, files, databases, and any external systems that provide data to the application.
Implementation · Input Validation
Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
OWASP Cheat Sheets
Abuse Case (opens in a new tab)
Deserialization (opens in a new tab)
Injection Prevention (opens in a new tab)
SQL Injection Prevention (opens in a new tab)
Injection Prevention in Java (opens in a new tab)
OWASP ASVS 4.0.3
V1.5.1 (opens in a new tab)
Attack patterns
Flash Parameter Injection (opens in a new tab)
Using Meta-characters in E-mail Headers to Inject Malicious Payloads (opens in a new tab)
HTTP Parameter Pollution (HPP) (opens in a new tab)
OS Command Injection (opens in a new tab)
Parameter Injection (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 7 Jul 2025, 08:26 UTC

WeaknessesCWE-88

Technical details

References

Community reviews

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