CVE-2019-12523: canonical ubuntu_linux
Vulnerability summary
CVE-2019-12523 is a critical (CVSS 9.1) vulnerability in canonical ubuntu_linux. EPSS estimates a 4.30% chance of exploitation in the next 30 days, higher than 91% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 14 · Related 10Timeline
- 26-11-2019PublishedVulnerability first disclosed.
- 04-08-2024Last modifiedVulnerability information updated.
Description
An issue was discovered in Squid before 4.9. When handling a URN request, a corresponding HTTP request is made. This HTTP request doesn't go through the access checks that incoming HTTP requests go through. This causes all access checks to be bypassed and allows access to restricted HTTP servers, e.g., an attacker can connect to HTTP servers that only listen on localhost.
CVSS metrics
4 scores · 3 sources · 2 versions- OSV · UbuntuEcosystem advisory · calculated9.1CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
- OSV · DebianEcosystem advisory · calculated9.1CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
EPSS trend
Probability
4.30%
Chance of exploitation in the next 30 days
Percentile
91%
Versus all other CVEs
30-day change
0.00 pp
From 4.30% on 18-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeNo weakness data has been published for this record.
Affected systems
Debian2 products
- squid< 4.9-1
- debian_linuxEOL9.0 | 10.0
Ubuntu2 products
- squid< 4.9-2ubuntu1
- squid3< 3.5.12-1ubuntu7.12 | < 3.5.27-1ubuntu1.7
Canonical1 product
- ubuntu_linuxEOL16.04 | 18.04 | 19.04 | 19.10
Fedoraproject1 product
- fedoraEOL30 | 31
Opensuse1 product
- leapEOL15.0
Squid-cache1 product
- squid≥ 3.0, ≤ 3.5.28 | ≥ 4.0, ≤ 4.8
6 vendors · 8 products
References
14 links
- lists.debian.org/debian-lts-announce/2020/07/msg00009.htmlMailing ListX Refsource MLISTThird Party Advisory