CVE-2026-55618
MediumCVSS 6.5Exploitation Probability (EPSS)
Low risk22th percentile - higher than 22% of all known CVEs
Summary
eml_parser before version 3.0.2 contains a vulnerability in the clean_found_uri function that incorrectly validates URLs before unescaping HTML entities for colon, slash, or period characters. As a result, valid encoded URLs and their hostnames are rejected and omitted from extracted URL and domain lists. Email security gateways and SOC pipelines using these lists as indicators of compromise may fail to submit hidden URLs to threat intelligence feeds, reputation services, or sandboxes, allowing malicious links to bypass inspection.
Risk Assessment
The risk is that malicious URLs may not be detected and submitted for analysis, allowing attackers to bypass security measures and deliver malicious content.
Recommendation
It is recommended to update eml_parser to version 3.0.2 or later, which includes a fix ensuring proper processing of encoded URLs.
Other vulnerabilities in eml_parser
See all- CVE-2026-55620High
eml_parser before version 3.0.2 has a quadratic-time regex-based loop in the noparenthesis function when processing Received: headers with nested parentheses. A single header with 5000 nested parentheses causes about 1.3 seconds of CPU saturation per message, and doubling the nesting depth quadruples the running time. Attackers can submit small EML files that consume multiple seconds of processing time, causing latency and potential outages.
- CVE-2026-55619Medium
eml_parser before version 3.0.2 contains a stack overflow vulnerability in the header_fetch_parse function when parsing nested CFWS constructs in email headers. An attacker can send a specially crafted EML file that causes an unhandled RecursionError and aborts parsing of the entire message. This can disrupt SOC pipelines processing untrusted EML files.
- CVE-2026-44844Medium
In eml_parser before version 3.0.1, the EmlParser.get_raw_body_text() function recursively processes nested message/rfc822 attachments without any depth limit. An attacker can supply a crafted EML file with approximately 120 nested parts, causing an unhandled RecursionError and aborting parsing.
Original NVD description (English source)
eml_parser serves as a python module for parsing eml files and returning various information found in the e-mail as well as computed information. Prior to 3.0.2, the clean_found_uri function in eml_parser/parser.py validates potential URL strings before unescaping HTML entities used for colon, slash, or period characters. Valid encoded URLs and their host names are therefore rejected and omitted from the extracted URL and domain lists. Email security gateways and SOC pipelines that use those lists as indicators of compromise may fail to submit the hidden URLs to threat intelligence feeds, reputation services, or sandboxes, allowing malicious links to bypass inspection. This issue is fixed in version 3.0.2.