VulnerabilityPublished 17 Dec 2025

CVE-2024-29370: python-jose · CVE-2024-29370 is a medium severity

Affects python-joseSource CVE Database V5

Not known to be exploited · CVSS 5.3 Medium.

Data as of 26 Oct 2026, 13:47 UTC

CVSS 3.1 base score

5.3Medium

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

EPSS: 0.1% chance of exploitation in 30 days – higher than 8% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

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

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: None
Scope: Unchanged
Confidentiality: None
Integrity: None
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: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
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: None: There is no loss of confidentiality within the impacted component.
Integrity: None: There is no loss of integrity within 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 17 Dec 2025
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 26 Oct 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.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, 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
PyPIpython-jose`pkg:pypi/python-jose`Other threats	Affected =3.3.0	Fixed in–

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

AI-suggested

Monitor python-jose project repositories and security advisories for official patches or updates addressing CVE-2024-29370 and apply them promptly once available.
Implement input validation and rate limiting on endpoints that accept JWE tokens to detect and block tokens with suspiciously high compression ratios or abnormal sizes.
Employ resource usage monitoring and set strict memory and CPU usage limits for services handling JWE decryption to prevent resource exhaustion.
Consider using alternative libraries or updated versions of python-jose that are not affected by this vulnerability if immediate patching is not possible.
Deploy Web Application Firewalls (WAFs) with custom rules to detect and block malformed or malicious JWE tokens.
Conduct security testing and fuzzing on token processing components to identify and mitigate similar resource exhaustion risks.
Educate development teams about secure handling of compressed data and the risks of decompression bombs.
Isolate critical services and implement failover mechanisms to maintain availability during potential DoS attempts.

Description

CVE-2024-29370 is a medium severity vulnerability in python-jose 3.3.0's JWE decryption function that allows an attacker to cause a Denial-of-Service (DoS) by sending a malicious JSON Web Encryption token with an extremely high compression ratio. This crafted token triggers excessive memory allocation and processing time during decompression, potentially exhausting server resources. The vulnerability requires no authentication or user interaction and can be exploited remotely over the network. While no known exploits are currently reported in the wild, affected systems processing untrusted JWE tokens are at risk. The CVSS score is 5.3, reflecting a moderate impact on availability without affecting confidentiality or integrity. European organizations using python-jose for JWE token handling in web services or APIs should prioritize mitigation to prevent service disruption. No official patches are available yet, so defensive measures are critical.

Impact

For European organizations, this vulnerability poses a risk of service disruption due to resource exhaustion when processing malicious JWE tokens. Organizations that use python-jose 3.3.0 in their authentication or API token handling mechanisms could experience degraded performance or outages, impacting availability of critical services. This could affect sectors such as finance, healthcare, government, and e-commerce, where secure token-based authentication is common. The DoS condition does not compromise confidentiality or integrity but can lead to denial of legitimate user access, potentially causing operational and reputational damage. Since the attack requires no authentication and can be launched remotely, the threat is significant for internet-facing services. The lack of known exploits in the wild reduces immediate risk, but the presence of a public CVE and medium severity score means attackers may develop exploits in the future. European organizations with high dependency on Python-based web frameworks and microservices architectures are particularly vulnerable.

CWE-409Improper Handling of Highly Compressed Data (Data Amplification) (opens in a new tab)
Base weakness
The product does not handle or incorrectly handles a compressed input with a very high compression ratio that produces a large output.
OWASP Cheat Sheets
File Upload (opens in a new tab)
OWASP ASVS 4.0.3
V12.1.2 (opens in a new tab)
V12.1.1 (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

github.com/mpdavis/python-jose/issues/344 (opens in a new tab)

Community reviews

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 24 Dec 2025, 17:06 UTC

WeaknessesCWE-409

Technical details

References

Community reviews

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