Buffer overflow in Squid-Cache Squid
CVE-2019-12525
An issue was discovered in Squid 3.3.9 through 3.5.28 and 4.x through 4.7. When Squid is configured to use Digest authentication, it parses the header Proxy-Authorization. It searches for certain tokens such as domain, uri, and qop. Squid checks if this token's value starts with a quote and ends with one. If so, it performs a memcpy of its length minus 2. Squid never checks whether the value is just a single quote (which would satisfy its requirements), leading to a memcpy of its length minus 1.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.244 (97.8th percentile), scored .
Moderate probability of exploitation in the next 30 days — watch for active exploitation reports. 98th percentile — 97.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.244 · newest: 0.244 · change: 0.000
Affected products
- Squid-Cache Squid
- Canonical Ubuntu Linux — versions 12.04, 16.04, 18.04
- Debian Linux — versions 8.0, 9.0, 10.0
- Fedoraproject Fedora — versions 29
- openSUSE Leap — versions 15.0, 15.1
Weakness classification (CWE)
Public proof-of-concept exploits
References
- www.squid-cache.org/Versions/v4/changesets/ (Vendor Advisory)
- github.com/squid-cache/squid/commits/v4 (Patch, Third Party Advisory)
- www.squid-cache.org/Versions/v4/changesets/squid-4-7f73e9c5d17664b882ed32590e6a… (Patch, Vendor Advisory)
- usn.ubuntu.com/4065-1/ (vendor-advisory, Third Party Advisory)
- lists.debian.org/debian-lts-announce/2019/07/msg00018.html (mailing-list, Mailing List, Third Party Advisory)
- usn.ubuntu.com/4065-2/ (vendor-advisory, Third Party Advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
- www.debian.org/security/2019/dsa-4507 (vendor-advisory, Third Party Advisory)
- seclists.org/bugtraq/2019/Aug/42 (mailing-list, Mailing List, Third Party Advisory)
- lists.opensuse.org/opensuse-security-announce/2019-11/msg00053.html (vendor-advisory, Mailing List, Third Party Advisory)
Frequently asked questions
- What is CVE-2019-12525?
- CVE-2019-12525 is a critical-severity vulnerability in Squid-Cache Squid, classified under Out-of-bounds Write. CVSS score: 9.8/10. Published 2019-07-11.
- How severe is CVE-2019-12525?
- Critical severity. CVSS v3 base score is 9.8 out of 10.
- Is CVE-2019-12525 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.