CVE-2019-12527
CVE-2019-12527 is a high-severity vulnerability in Squid-cache Squid with a CVSS 3.x base score of 8.8. Its EPSS exploit-prediction score of 50% places it in the 99th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-787.
Key facts
- Severity: High (CVSS 3.x base score 8.8)
- CVSS v2: 6.8
- EPSS exploit prediction: 50% (99th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-787
- Affected product: Squid-cache Squid
- Published:
- Last modified:
Description
An issue was discovered in Squid 4.0.23 through 4.7. When checking Basic Authentication with HttpHeader::getAuth, Squid uses a global buffer to store the decoded data. Squid does not check that the decoded length isn't greater than the buffer, leading to a heap-based buffer overflow with user controlled data.
Frequently asked questions
- What is CVE-2019-12527?
- An issue was discovered in Squid 4.0.23 through 4.7. When checking Basic Authentication with HttpHeader::getAuth, Squid uses a global buffer to store the decoded data. Squid does not check that the decoded length isn't greater than the buffer, leading to a heap-based buffer overflow with user controlled data.
- How severe is CVE-2019-12527?
- CVE-2019-12527 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2019-12527 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 50% (99th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2019-12527?
- CVE-2019-12527 primarily affects Squid-cache Squid. In total, 17 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2019-12527?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2019-12527 published?
- CVE-2019-12527 was published on 2019-07-11 and last updated on 2026-06-17.
References
- http://lists.opensuse.org/opensuse-security-announce/2019-11/msg00053.html
- http://lists.opensuse.org/opensuse-security-announce/2019-11/msg00056.html
- http://www.securityfocus.com/bid/109143
- http://www.squid-cache.org/Versions/v4/changesets/
- http://www.squid-cache.org/Versions/v4/changesets/squid-4-7f73e9c5d17664b882ed32590e6af310c247f320.patch
- https://access.redhat.com/errata/RHSA-2019:2593
- https://github.com/squid-cache/squid/commits/v4
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SPXN2CLAGN5QSQBTOV5IGVLDOQSRFNTZ/
- https://seclists.org/bugtraq/2019/Aug/42
- https://usn.ubuntu.com/4065-1/
- https://www.debian.org/security/2019/dsa-4507
Affected products (17)
- cpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:*
- cpe:2.3:o:fedoraproject:fedora:29:*:*:*:*:*:*:*
- cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
- cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:esm:*:*:*
- cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:*
- cpe:2.3:o:canonical:ubuntu_linux:19.04:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux_eus:8.1:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux_eus:8.2:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux_eus:8.4:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux_eus:8.6:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux_server_aus:8.2:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux_server_aus:8.4:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux_server_aus:8.6:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux_server_tus:8.2:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux_server_tus:8.4:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux_server_tus:8.6:*:*:*:*:*:*:*
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