CVE-2019-18676An issue was discovered in Squid 3.x and 4.x through 4.8. Due to incorrect input validation, there is a heap-based buffer overflow that…
- 7.5HighCVSS base score
- 9.2%Exploitation in 30 daysEPSS · top 4.6% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
An issue was discovered in Squid 3.x and 4.x through 4.8. Due to incorrect input validation, there is a heap-based buffer overflow that can result in Denial of Service to all clients using the proxy. Severity is high due to this vulnerability occurring before normal security checks; any remote client that can reach the proxy port can trivially perform the attack via a crafted URI scheme.
Timeline
ID reserved
By mitre
- 22 days later
· 22 days later
Published
- 5 years later
· 5 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 9.2% · top 4.6% of all CVEs (12 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.5.
Affected products
n/a
- affected n/a
References
References10
- https://github.com/squid-cache/squid/pull/275 (opens in a new tab)x_refsource_MISCx_transferred
- http://www.squid-cache.org/Advisories/SQUID-2019_8.txt (opens in a new tab)x_refsource_CONFIRMx_transferred
- https://bugzilla.suse.com/show_bug.cgi?id=1156329 (opens in a new tab)x_refsource_CONFIRMx_transferred
- http://www.squid-cache.org/Versions/v4/changesets/squid-4-fbbdf75efd7a5cc244b4886a9d42ea458c5a3a73.patch (opens in a new tab)x_refsource_CONFIRMx_transferred
- USN-4213-1 (opens in a new tab)vendor-advisoryx_refsource_UBUNTUx_transferred
- FEDORA-2019-0b16cbdd0e (opens in a new tab)vendor-advisoryx_refsource_FEDORAx_transferred
- FEDORA-2019-9538783033 (opens in a new tab)vendor-advisoryx_refsource_FEDORAx_transferred
- DSA-4682 (opens in a new tab)vendor-advisoryx_refsource_DEBIANx_transferred
- [debian-lts-announce] 20200710 [SECURITY] [DLA 2278-1] squid3 security update (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
- USN-4446-1 (opens in a new tab)vendor-advisoryx_refsource_UBUNTUx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2019-8392 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2019-18676)Record last updated .