CVE-2019-16056

An issue was discovered in Python through 2.7.16, 3.x through 3.5.7, 3.6.x through 3.6.9, and 3.7.x through 3.7.4. The email module wrongly parses email addresses that contain multiple @ characters. An application that uses the email module and implements some kind of checks on the From/To headers of a message could be tricked into accepting an email address that should be denied. An attack may be the same as in CVE-2019-11340; however, this CVE applies to Python more generally.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
python2.7	24.10 oracular	Not in release
	24.04 LTS noble	Not in release
	23.10 mantic	Not in release
	23.04 lunar	Not in release
	22.10 kinetic	Not affected
	22.04 LTS jammy	Not affected
	21.10 impish	Not affected
	21.04 hirsute	Not affected
	20.10 groovy	Not affected
	20.04 LTS focal	Not affected
	19.10 eoan	Not affected
	19.04 disco	Fixed 2.7.16-2ubuntu0.2
	18.04 LTS bionic	Fixed 2.7.15-4ubuntu4~18.04.2
	16.04 LTS xenial	Fixed 2.7.12-1ubuntu0~16.04.9
	14.04 LTS trusty	Fixed 2.7.6-8ubuntu0.6+esm3 Ubuntu Pro
python3.4	24.10 oracular	Not in release
	24.04 LTS noble	Not in release
	23.10 mantic	Not in release
	23.04 lunar	Not in release
	22.10 kinetic	Not in release
	22.04 LTS jammy	Not in release
	21.10 impish	Not in release
	21.04 hirsute	Not in release
	20.10 groovy	Not in release
	20.04 LTS focal	Not in release
	19.10 eoan	Not in release
	19.04 disco	Not in release
	18.04 LTS bionic	Not in release
	16.04 LTS xenial	Not in release
	14.04 LTS trusty	Fixed 3.4.3-1ubuntu1~14.04.7+esm4 Ubuntu Pro
python3.5	24.10 oracular	Not in release
	24.04 LTS noble	Not in release
	23.10 mantic	Not in release
	23.04 lunar	Not in release
	22.10 kinetic	Not in release
	22.04 LTS jammy	Not in release
	21.10 impish	Not in release
	21.04 hirsute	Not in release
	20.10 groovy	Not in release
	20.04 LTS focal	Not in release
	19.10 eoan	Not in release
	19.04 disco	Not in release
	18.04 LTS bionic	Not in release
	16.04 LTS xenial	Fixed 3.5.2-2ubuntu0~16.04.9
	14.04 LTS trusty	Fixed 3.5.2-2ubuntu0~16.04.4~14.04.1+esm1 Ubuntu Pro
python3.6	24.10 oracular	Not in release
	24.04 LTS noble	Not in release
	23.10 mantic	Not in release
	23.04 lunar	Not in release
	22.10 kinetic	Not in release
	22.04 LTS jammy	Not in release
	21.10 impish	Not in release
	21.04 hirsute	Not in release
	20.10 groovy	Not in release
	20.04 LTS focal	Not in release
	19.10 eoan	Not in release
	19.04 disco	Not in release
	18.04 LTS bionic	Fixed 3.6.8-1~18.04.3
	16.04 LTS xenial	Not in release
	14.04 LTS trusty	Not in release
python3.7	24.10 oracular	Not in release
	24.04 LTS noble	Not in release
	23.10 mantic	Not in release
	23.04 lunar	Not in release
	22.10 kinetic	Not in release
	22.04 LTS jammy	Not in release
	21.10 impish	Not in release
	21.04 hirsute	Not in release
	20.10 groovy	Not in release
	20.04 LTS focal	Not in release
	19.10 eoan	Not affected
	19.04 disco	Fixed 3.7.3-2ubuntu0.2
	18.04 LTS bionic	Not affected
	16.04 LTS xenial	Not in release
	14.04 LTS trusty	Not in release

Get expanded security coverage with Ubuntu Pro

Reduce your average CVE exposure time from 98 days to 1 day with expanded CVE patching, ten-years security maintenance and optional support for the full stack of open-source applications. Free for personal use.

Get Ubuntu Pro

Notes

seth-arnold

This has a very high risk of regression. Email addresses should not be validated beyond making sure there’s at least one byte on both sides of an ‘@’ sign. Legal email addresses are significantly more complicated than what is easy to express in regex. Whatever validation this module provides is in my opinion suspect.

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package	Patch details
python2.7	Upstream: 4cbcd2f
python3.5	Upstream: 063eba2
python3.6	Upstream: 13a1913
python3.7	Upstream: c48d606

Severity score breakdown

Parameter	Value
Base score	7.5 · High
Attack vector	Network
Attack complexity	Low
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality	High
Integrity impact	None
Availability impact	None
Vector	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

References

Related Ubuntu Security Notices (USN)

USN-4151-1
Python vulnerabilities
9 October 2019

USN-4151-2
Python vulnerabilities
10 October 2019

USN-6891-1
Python vulnerabilities
11 July 2024

Other references

https://www.cve.org/CVERecord?id=CVE-2019-16056