CVE-2017-9951
CVE-2017-9951 is a high-severity vulnerability in Memcached with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.
Key facts
- Severity: High (CVSS 3.x base score 7.5)
- CVSS v2: 5.0
- EPSS exploit prediction: 4% (90th percentile)
- Actively exploited: Not listed in CISA KEV
- Affected product: Memcached
- Published:
- Last modified:
Description
The try_read_command function in memcached.c in memcached before 1.4.39 allows remote attackers to cause a denial of service (segmentation fault) via a request to add/set a key, which makes a comparison between signed and unsigned int and triggers a heap-based buffer over-read. NOTE: this vulnerability exists because of an incomplete fix for CVE-2016-8705.
Frequently asked questions
- What is CVE-2017-9951?
- The try_read_command function in memcached.c in memcached before 1.4.39 allows remote attackers to cause a denial of service (segmentation fault) via a request to add/set a key, which makes a comparison between signed and unsigned int and triggers a heap-based buffer over-read. NOTE: this vulnerability exists because of an incomplete fix for CVE-2016-8705.
- How severe is CVE-2017-9951?
- CVE-2017-9951 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
- Is CVE-2017-9951 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (90th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2017-9951?
- CVE-2017-9951 affects Memcached. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2017-9951?
- 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-2017-9951 published?
- CVE-2017-9951 was published on 2017-07-17 and last updated on 2026-06-17.
References
- http://www.securityfocus.com/bid/99874
- https://github.com/memcached/memcached/wiki/ReleaseNotes1439
- https://groups.google.com/forum/message/raw?msg=memcached/ubGWrkmrr4E/nrm1SeVJAQAJ
- https://usn.ubuntu.com/3588-1/
- https://www.debian.org/security/2018/dsa-4218
- https://www.twistlock.com/2017/07/13/cve-2017-9951-heap-overflow-memcached-server-1-4-38-twistlock-vulnerability-report/
Affected products (1)
- cpe:2.3:a:memcached:memcached:*:*:*:*:*:*:*:*
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