CVE-2018-6340 json
The Memcache::getextendedstats function can be used to trigger an out-of-bounds read.
published 2018-12-31 7 y ago modified 2026-06-17 4 mo ago also EUVD-2018-18100
- cvss
- 8.1
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.4%
- EPSS 1.4% chance of exploitation in 30 days, percentile 73%
- public exploits
- 0
- none known
Summary
The Memcache::getextendedstats function can be used to trigger an out-of-bounds read. Exploiting this issue requires control over memcached server hostnames and/or ports. This affects all supported versions of HHVM (3.30 and 3.27.4 and below).
Patch / fix
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- 18 mo ago
Exploit prediction
1.43% chance of exploitation in the next 30 days, higher than 73% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CISA ADP | 3.1 | 8.1 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H |
| CNA | 3.1 | 8.1 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVD | 3.0 | 8.1 | CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVD | 2.0 | 6.8 | AV:N/AC:M/Au:N/C:P/I:P/A:P |
Affected products
- Facebook HHVM
Classification
- Weakness
-
- CWE-125 Out-of-bounds Read
References
-
github.com
/facebook/hhvm/commit/4bff3bfbe90d10451e4638c2118d1ad1117bb3e3
patch, third-party-advisory
-
hhvm.com
/blog/2018/12/18/hhvm-3.30.1.html
third-party-advisory
Sources
- CVE List CVE-2018-6340
- NVD CVE-2018-6340
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