CRLF Injection Affecting cpython package, versions [0,]
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-CONAN-CPYTHON-15279051
- published13 Feb 2026
- disclosed23 Jan 2026
- creditUnknown
Introduced: 23 Jan 2026
CVE-2026-1299 (opens in a new tab)How to fix?
A fix was pushed into the master branch but not yet published.
Overview
Affected versions of this package are vulnerable to CRLF Injection via the BytesGenerator class in the email module due to unquoted newlines when serializing an email message. An attacker could perform email spoofing, data exfiltration, or content manipulation by injecting malicious CRLF sequences into headers.
Note:
This is only exploitable if using LiteralHeader writing headers that don't respect email folding rules.