SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2016-8622

The URL percent-encoding decode function in libcurl before 7.51.0 is called `curl_easy_unescape`.

CRITICAL 9.8EPSS 4.67%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (4.67%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

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 3.0
9.8 CRITICALCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
4.67% probability · 91th percentile
CISA KEV
Not listed
Weakness
CWE-122, CWE-190, CWE-787
Affected
haxx/libcurl
Source
secalert@redhat.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.