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TI-2016-07084 Aliases CVE-2016-8622GHSA-xfmx-53v5-938g

Heap-based buffer overflow in curl

Priority MEDIUM 50CWE-122Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 8 fixed, 7 without a fix

Attack profile from CVSS 3.0 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-122 and the CVSS impact.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0467 91st percentileScored 2026-11-07
Fix Partial Red Hat: 2 advisoriesRed Hat: 8 fixed, 7 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
The Curl Projectcurl7.51.0—No fix listedCNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:haxx:libcurl:*:*:*:*:*:*:*:*before 7.51.0VulnerableHaxx
  • cpe:2.3:a:haxx:libcurl:*:*:*:*:*:*:*:* Versions before 7.51.0 Vulnerable ·Haxx

Remediation

Red Hat 2 advisories

  • RHSA-2018:3558 Released 2018-11-13 · Red Hat rating Moderate
    httpd24 security, bug fix, and enhancement update
    • Red Hat Software Collections for Red Hat Enterprise Linux Server (v. 6) httpd24-curl-7.61.1-1.el6, httpd24-httpd-2.4.34-7.el6, httpd24-httpd-devel-2.4.34-7.el6 +11
    • Red Hat Software Collections for Red Hat Enterprise Linux Server (v. 7) httpd24-curl-7.61.1-1.el7, httpd24-httpd-2.4.34-7.el7, httpd24-httpd-devel-2.4.34-7.el7 +12
    • Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.4) httpd24-curl-7.61.1-1.el7, httpd24-httpd-2.4.34-7.el7, httpd24-httpd-devel-2.4.34-7.el7 +12
    • Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.5) httpd24-curl-7.61.1-1.el7, httpd24-httpd-2.4.34-7.el7, httpd24-httpd-devel-2.4.34-7.el7 +12
    • Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.6) httpd24-curl-7.61.1-1.el7, httpd24-httpd-2.4.34-7.el7, httpd24-httpd-devel-2.4.34-7.el7 +12
    • Red Hat Software Collections for Red Hat Enterprise Linux Workstation (v. 6) httpd24-curl-7.61.1-1.el6, httpd24-httpd-2.4.34-7.el6, httpd24-httpd-devel-2.4.34-7.el6 +11
    • Red Hat Software Collections for Red Hat Enterprise Linux Workstation (v. 7) httpd24-curl-7.61.1-1.el7, httpd24-httpd-2.4.34-7.el7, httpd24-httpd-devel-2.4.34-7.el7 +12
  • RHSA-2018:2486 Released 2018-08-16 · Red Hat rating Important
    Red Hat JBoss Core Services Apache HTTP Server 2.4.29 security update
    • Red Hat JBoss Core Services

Vendor assessments

Red Hat

Red Hat rating: Low. Red Hat's page for this CVE →

ProductStatusPlan or fix
.NET Core 1.0 on Red Hat Enterprise LinuxAffectedNo fix planned: Out of support scope
.NET Core 1.1 on Red Hat Enterprise LinuxAffectedNo fix planned: Out of support scope
.NET Core 2.0 on Red Hat Enterprise LinuxAffectedNo fix planned: Out of support scope
.NET Core 2.1 on Red Hat Enterprise LinuxAffectedNo fix planned: Will not fix
Red Hat Enterprise Linux 7AffectedNo fix planned: Will not fix
Red Hat Enterprise Virtualization 3AffectedNo fix planned: Will not fix
Red Hat JBoss Enterprise Web Server 3AffectedNo fix yet: Fix deferred
Red Hat JBoss Core ServicesFixed RHSA-2018:2486
Red Hat Software Collections for Red Hat Enterprise Linux Server (v. 6)Fixed RHSA-2018:3558
Red Hat Software Collections for Red Hat Enterprise Linux Server (v. 7)Fixed RHSA-2018:3558
Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.4)Fixed RHSA-2018:3558
Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.5)Fixed RHSA-2018:3558
Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.6)Fixed RHSA-2018:3558
Red Hat Software Collections for Red Hat Enterprise Linux Workstation (v. 6)Fixed RHSA-2018:3558
Red Hat Software Collections for Red Hat Enterprise Linux Workstation (v. 7)Fixed RHSA-2018:3558
Not affected: 2 products
  • Red Hat Enterprise Linux 5
  • Red Hat Enterprise Linux 6

Timeline

  1. 2026-10-02 Threatist record created from CVE-2016-8622
  2. 2026-10-03 Alias added: GHSA-xfmx-53v5-938g

References

Patch 2

Advisory 4

Other 1

  • TI-2019-02834 Stack-based buffer overflow in curl CVSS 3.1CRITICAL 9.8
  • TI-2016-07082 Buffer overflow in curl CVSS 3.0CRITICAL 9.8
  • TI-2018-12049 Heap-based buffer overflow in curl: CVSS 3.0CRITICAL 9.8
  • TI-2016-07081 The function `read_data()` in security.c in curl before version 7.51.0 is vulnerable to memory double free. CVSS 3.0CRITICAL 9.8
  • TI-2016-07080 Use after free in curl CVSS 3.0CRITICAL 9.8
  • TI-2018-12050 Use after free in curl CVSS 3.1CRITICAL 9.8
See all 17 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences