USN-4886-1: Privoxy vulnerabilities

Releases

• Ubuntu 20.10
• Ubuntu 20.04 LTS
• Ubuntu 18.04 ESM
• Ubuntu 16.04 ESM
• Ubuntu 14.04 ESM

Packages

• privoxy - Privacy enhancing HTTP Proxy

Details

It was discovered that Privoxy incorrectly handled CGI requests. An attacker
could possibly use this issue to cause a denial of service or obtain sensitive
information. (CVE-2020-35502, CVE-2021-20209, CVE-2021-20210,
CVE-2021-20213, CVE-2021-20215, CVE-2021-20216, CVE-2021-20217,
CVE-2021-20272, CVE-2021-20273, CVE-2021-20275)

It was discovered that Privoxy incorrectly handled certain regular
expressions. An attacker could possibly use this issue to cause a denial of
service or obtain sensitive information. (CVE-2021-20212, CVE-2021-20276)

It was discovered that Privoxy incorrectly handled client tags. An attacker
could possibly use this issue to cause Privoxy to consume resources, resulting
in a denial of service. This issue only affected Ubuntu 18.04 LTS,
Ubuntu 20.04 LTS and Ubuntu 20.10. (CVE-2021-20211)

It was discovered that Privoxy incorrectly handled client tags. An attacker
could possibly use this issue to cause Privoxy to consume resources, resulting
in a denial of service. This issue only affected Ubuntu 20.04 LTS and
Ubuntu 20.10. (CVE-2021-20214)

Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 20.10

• privoxy - 3.0.28-3ubuntu0.1

Ubuntu 20.04

• privoxy - 3.0.28-2ubuntu0.1

Ubuntu 18.04

• privoxy - 3.0.26-5ubuntu0.1

Ubuntu 16.04

• privoxy - 3.0.24-1ubuntu0.1

Ubuntu 14.04

• privoxy - 3.0.21-7+deb8u1ubuntu0.1~esm1
  Available with Ubuntu Pro

In general, a standard system update will make all the necessary changes.

References

• CVE-2021-20213
• CVE-2021-20215
• CVE-2021-20212
• CVE-2021-20211
• CVE-2021-20276
• CVE-2020-35502
• CVE-2021-20216
• CVE-2021-20210
• CVE-2021-20209
• CVE-2021-20217
• CVE-2021-20273
• CVE-2021-20275
• CVE-2021-20272
• CVE-2021-20214