CVE-2018-1000027
The Squid Software Foundation Squid HTTP Caching Proxy version prior to version 4.0.23 contains a NULL Pointer Dereference vulnerability…
- 7.5HighCVSS base score
- 12.9%Exploitation in 30 daysEPSS · top 3.6% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
The Squid Software Foundation Squid HTTP Caching Proxy version prior to version 4.0.23 contains a NULL Pointer Dereference vulnerability in HTTP Response X-Forwarded-For header processing that can result in Denial of Service to all clients of the proxy. This attack appear to be exploitable via Remote HTTP server responding with an X-Forwarded-For header to certain types of HTTP request. This vulnerability appears to have been fixed in 4.0.23 and later.
Timeline
ID reserved
By mitre
- 11 days later
· 11 days later
Published
- 6 years later
· 6 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 | 3.0 | High7.5 | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 12.9% · top 3.6% of all CVEs (11 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
References9
- USN-3557-1 (opens in a new tab)vendor-advisoryx_refsource_UBUNTUx_transferred
- http://www.squid-cache.org/Versions/v4/changesets/SQUID-2018_2.patch (opens in a new tab)x_refsource_CONFIRMx_transferred
- DSA-4122 (opens in a new tab)vendor-advisoryx_refsource_DEBIANx_transferred
- http://www.squid-cache.org/Advisories/SQUID-2018_2.txt (opens in a new tab)x_refsource_CONFIRMx_transferred
- [debian-lts-announce] 20180202 [SECURITY] [DLA 1266-1] squid3 security update (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
- https://github.com/squid-cache/squid/pull/129/files (opens in a new tab)x_refsource_CONFIRMx_transferred
- http://www.squid-cache.org/Versions/v3/3.5/changesets/SQUID-2018_2.patch (opens in a new tab)x_refsource_CONFIRMx_transferred
- [debian-lts-announce] 20180202 [SECURITY] [DLA 1267-1] squid security update (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
- USN-4059-2 (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-2018-1788 (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-2018-1000027)Record last updated .