CVE-2016-8622

The URL percent-encoding decode function in libcurl before 7.51.0 is called `curl_easy_unescape`. Internally, even if this function would be made to allocate a unscape destination buffer larger than 2GB, it would return that new length in a signed 32 bit integer variable, thus the length would get either just truncated or both truncated and turned negative. That could then lead to libcurl writing outside of its heap based buffer.

CVSS v3.0 9.8 CRITICAL
CVSS v2.0 7.5 HIGH

9.8^/10

CVSS v3.0 : CRITICAL

Vector : AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

7.5^/10

CVSS v2.0 : HIGH

Vector : AV:N/AC:L/Au:N/C:P/I:P/A:P

Exploitability : 10.0 / Impact : 6.4

Access Vector NETWORK

Access Complexity LOW

Authentication NONE

Confidentiality Impact PARTIAL

Integrity Impact PARTIAL

Availability Impact PARTIAL

References

Link	Resource
https://curl.haxx.se/docs/adv_20161102H.html	Patch Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2016-8622	Issue Tracking Patch Third Party Advisory
https://www.tenable.com/security/tns-2016-21	Third Party Advisory
https://security.gentoo.org/glsa/201701-47	Third Party Advisory
http://www.securitytracker.com/id/1037192	Third Party Advisory VDB Entry
http://www.securityfocus.com/bid/94105	Third Party Advisory VDB Entry
https://access.redhat.com/errata/RHSA-2018:2486	Third Party Advisory
http://www.oracle.com/technetwork/security-advisory/cpuoct2018-4428296.html
https://access.redhat.com/errata/RHSA-2018:3558

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Configurations

Configuration 1 (hide)

cpe:2.3:a:haxx:libcurl:*:*:*:*:*:*:*:*

Information

Published : 2018-07-31 14:29

Updated : 2018-11-13 03:29

NVD link : CVE-2016-8622

Mitre link : CVE-2016-8622

JSON object : View

CWE

CWE-787

Out-of-bounds Write

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Products Affected

haxx

libcurl

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