CVE-2016-9953
CVE-2016-9953 is a critical-severity vulnerability in Haxx Curl with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-125.
Key facts
- Severity: Critical (CVSS 3.x base score 9.8)
- CVSS v2: 7.5
- EPSS exploit prediction: 2% (76th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-125
- Affected product: Haxx Curl
- Published:
- Last modified:
Description
The verify_certificate function in lib/vtls/schannel.c in libcurl 7.30.0 through 7.51.0, when built for Windows CE using the schannel TLS backend, allows remote attackers to obtain sensitive information, cause a denial of service (crash), or possibly have unspecified other impact via a wildcard certificate name, which triggers an out-of-bounds read.
Frequently asked questions
- What is CVE-2016-9953?
- The verify_certificate function in lib/vtls/schannel.c in libcurl 7.30.0 through 7.51.0, when built for Windows CE using the schannel TLS backend, allows remote attackers to obtain sensitive information, cause a denial of service (crash), or possibly have unspecified other impact via a wildcard certificate name, which triggers an out-of-bounds read.
- How severe is CVE-2016-9953?
- CVE-2016-9953 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2016-9953 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (76th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2016-9953?
- CVE-2016-9953 affects Haxx Curl. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2016-9953?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
- When was CVE-2016-9953 published?
- CVE-2016-9953 was published on 2018-03-12 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:a:haxx:curl:*:*:*:*:*:*:*:*
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