CVE-2016-9953
The verify_certificate function in lib/vtls/schannel.c in libcurl 7.30.0 through 7.51.0, when...
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
9.8
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.
- Record
CVE-2016-9953- CVSS 3.0
- 9.8 Critical
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - CVSS 2.0
- 7.5 High
AV:N/AC:L/Au:N/C:P/I:P/A:P - Weakness
- CWE-125
- Updated
- 2026-11-02
CVE List No score
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.
- Record
CVE-2016-9953- Updated
- 2026-11-02
EUVDEUVD-2016-10740 No score
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.
- Record
EUVD-2016-10740- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-72rm-6rfp-xgr9
9.8
The verify_certificate function in lib/vtls/schannel.c in libcurl 7.30.0 through 7.51.0, when...
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.
- Record
GHSA-72rm-6rfp-xgr9- CVSS 3.0
- 9.8 Critical
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-125
- Updated
- 2026-11-02
OSVALPINE-CVE-2016-9953
9.8
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.
- Record
ALPINE-CVE-2016-9953- CVSS 3.0
- 9.8 Critical
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVBELL-CVE-2016-9953
9.8
CVE-2016-9953 does not affect BellSoft software
- Record
BELL-CVE-2016-9953- CVSS 3.0
- 9.8 Critical
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSV
9.8
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.
- Record
CVE-2016-9953- CVSS 3.0
- 9.8 Critical
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVCURL-CVE-2016-9953 No score
Win CE Schannel cert name out of buffer read
curl's TLS server certificate checks are flawed on Windows CE.
This vulnerability occurs in the verify certificate function when comparing a
wildcard certificate name (as returned by the Windows API function
CertGetNameString() to the hostname used to make the connection to the
server.
The pattern matching logic exhibits an out of bounds read. If the wildcard certificate name field is longer than the connection hostname, the wildcard comparison code performs an access out of bounds of the connection hostname heap based buffer. This issue could technically leak the contents of memory immediately preceding the connection hostname buffer, a crash or at worst happen to match against another piece of data.
- Record
CURL-CVE-2016-9953- Updated
- 2026-11-02
Affected products
Affected packages
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2016-9953 is a critical vulnerability (CVSS 9.8) in Haxx Curl, published December 21, 2016. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.80%, the 78th percentile. Fixed in curl 7.52.1-r0.