Summary
Denial of service in CBOR library
Workarounds
Again, users should use the latest version of this library.
In the meantime, note that the inputs affected by this issue are all CBOR maps or contain CBOR maps. An input that decodes to a single CBOR object is not capable of containing a CBOR map if—
- it begins with a byte other than 0x80 through 0xDF, or
- it does not contain a byte in the range 0xa0 through 0xBF.
Such an input is not affected by this vulnerability and an application can choose to perform this check before passing it to a CBOR decoding mechanism.
For more information
If you have any questions or comments about this advisory:
- Open an issue in the CBOR repository.
Impact
Due to this library's use of an inefficient algorithm, it is vulnerable to a denial of service attack when a maliciously crafted input is passed to DecodeFromBytes or other CBOR decoding mechanisms in this library.
Affected versions include versions 4.0.0 through 4.5.0.
This vulnerability was privately reported to me.
CVE-2024-23684 has a CVSS score of 7.5 (High). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (4.5.1); upgrading removes the vulnerable code path.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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See it in your environmentNew to Kodem? Get a demo →Remediation advice
This issue has been fixed in version 4.5.1. Users should use the latest version of this library. (The latest version is not necessarily 4.5.1. Check the README for this library's repository to see the latest version's version number.)
Frequently Asked Questions
- What is CVE-2024-23684? CVE-2024-23684 is a high-severity security vulnerability in com.upokecenter:cbor (maven), affecting versions >= 4.0.0, < 4.5.1. It is fixed in 4.5.1.
- How severe is CVE-2024-23684? CVE-2024-23684 has a CVSS score of 7.5 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Which versions of com.upokecenter:cbor are affected by CVE-2024-23684? com.upokecenter:cbor (maven) versions >= 4.0.0, < 4.5.1 is affected.
- Is there a fix for CVE-2024-23684? Yes. CVE-2024-23684 is fixed in 4.5.1. Upgrade to this version or later.
- Is CVE-2024-23684 exploitable, and should I be worried? Whether CVE-2024-23684 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2024-23684 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2024-23684? Upgrade
com.upokecenter:cborto 4.5.1 or later.