CVE-2020-15811

Published: 24 August 2020

An issue was discovered in Squid before 4.13 and 5.x before 5.0.4. Due to incorrect data validation, HTTP Request Splitting attacks may succeed against HTTP and HTTPS traffic. This leads to cache poisoning. This allows any client, including browser scripts, to bypass local security and poison the browser cache and any downstream caches with content from an arbitrary source. Squid uses a string search instead of parsing the Transfer-Encoding header to find chunked encoding. This allows an attacker to hide a second request inside Transfer-Encoding: it is interpreted by Squid as chunked and split out into a second request delivered upstream. Squid will then deliver two distinct responses to the client, corrupting any downstream caches.

Priority

Low

CVSS 3 base score: 6.5

Status

Package Release Status
squid
Launchpad, Ubuntu, Debian
Upstream Needs triage

Ubuntu 20.10 (Groovy Gorilla)
Released (4.13-1ubuntu1)
Ubuntu 20.04 LTS (Focal Fossa)
Released (4.10-1ubuntu1.2)
Ubuntu 18.04 LTS (Bionic Beaver) Does not exist

Ubuntu 16.04 LTS (Xenial Xerus) Does not exist

Ubuntu 14.04 ESM (Trusty Tahr) Does not exist

Ubuntu 12.04 ESM (Precise Pangolin) Does not exist

Patches:
Upstream: http://www.squid-cache.org/Versions/v4/changesets/SQUID-2020_8.patch
Upstream: https://github.com/squid-cache/squid/commit/fd68382860633aca92065e6c343cfd1b12b126e7
squid3
Launchpad, Ubuntu, Debian
Upstream Needs triage

Ubuntu 20.10 (Groovy Gorilla) Does not exist

Ubuntu 20.04 LTS (Focal Fossa) Does not exist

Ubuntu 18.04 LTS (Bionic Beaver)
Released (3.5.27-1ubuntu1.9)
Ubuntu 16.04 LTS (Xenial Xerus)
Released (3.5.12-1ubuntu7.15)
Ubuntu 14.04 ESM (Trusty Tahr) Does not exist

Ubuntu 12.04 ESM (Precise Pangolin) Needs triage