CVE-2024-1455
mediumpriority · track · 24EPSS 0.008 · 55 %ileEUUSEPSS · scored 2026-10-28
A vulnerability in the langchain-ai/langchain repository allows for a Billion Laughs Attack, a type of XML External Entity (XXE) exploitation. By nesting multiple layers of entities within an XML document, an attacker can cause the XML parser to consume excessive CPU and memory resources, leading to a denial of service (DoS).
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (4)
Products and version ranges known to be affected.
advisories (2)
Vendor and ecosystem advisories describing this.
- GHSA-q84m-rmw3-4382LangChain's XMLOutputParser vulnerable to XML Entity Expansion2024-03-26ghsa · osvUS
The XMLOutputParser in LangChain uses the etree module from the XML parser in the standard python library which has some XML vulnerabilities; see: https://docs.python.org/3/library/xml.html This primarily affects users that combine an LLM (or agent) with the `XMLOutputParser` and expose the component via an endpoint on a web-service. This would allow a malicious party to attempt to manipulate the LLM to produce a malicious payload for the parser that would compromise the availability of the service. A successful attack is predicated on: 1. Usage of XMLOutputParser 2. Passing of malicious input into the XMLOutputParser either directly or by trying to manipulate an LLM to do so on the users behalf 3. Exposing the component via a web-service
- PYSEC-2026-1519LangChain's XMLOutputParser vulnerable to XML Entity Expansion2026-07-07vendor · osvUS
The XMLOutputParser in LangChain uses the etree module from the XML parser in the standard python library which has some XML vulnerabilities; see: https://docs.python.org/3/library/xml.html This primarily affects users that combine an LLM (or agent) with the `XMLOutputParser` and expose the component via an endpoint on a web-service. This would allow a malicious party to attempt to manipulate the LLM to produce a malicious payload for the parser that would compromise the availability of the service. A successful attack is predicated on: 1. Usage of XMLOutputParser 2. Passing of malicious input into the XMLOutputParser either directly or by trying to manipulate an LLM to do so on the users behalf 3. Exposing the component via a web-service
also known as (6)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (7)
External citations — patches, advisories, analysis.
- https://cxsecurity.com/cveshow/CVE-2024-1455/cnnvd
- https://github.com/langchain-ai/langchain/commit/727d5023ce88e18e3074ef620a98137d26ff92a3cnnvd
- https://huntr.com/bounties/4353571f-c70d-4bfd-ac08-3a89cecb45b6cnnvd
- https://github.com/langchain-ai/langchain/commit/727d5023ce88e18e3074ef620a98137d26ff92a3enisa_euvd
- https://huntr.com/bounties/4353571f-c70d-4bfd-ac08-3a89cecb45b6enisa_euvd
- https://github.com/langchain-ai/langchain/commit/727d5023ce88e18e3074ef620a98137d26ff92a3Patchnvd
- https://huntr.com/bounties/4353571f-c70d-4bfd-ac08-3a89cecb45b6ExploitThird Party Advisorynvd
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