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TI-2018-12050 Aliases CVE-2018-16840GHSA-6vwf-m72q-cw8h

Use after free in curl

Priority MEDIUM 48CWE-416Published · 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: 1 fixed, 2 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-416 and the CVSS impact.

Summary

A heap use-after-free flaw was found in curl versions from 7.59.0 through 7.61.1 in the code related to closing an easy handle. When closing and cleaning up an 'easy' handle in the `Curl_close()` function, the library code first frees a struct (without nulling the pointer) and might then subsequently erroneously write to a struct field within that already freed struct.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.03398 88th percentileScored 2026-11-07
Fix Partial Red Hat: 1 advisoryRed Hat: 1 fixed, 2 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 Projectcurlfrom 7.59.0 to 7.61.1—No fix listedCNA
  • curl VendorThe Curl Project Affected from 7.59.0 to 7.61.1 Fixed in — No fix listed CNA

CPE configurations NVD · 5

CPEVersionsRoleVendor
cpe:2.3:a:haxx:curl:*:*:*:*:*:*:*:*7.59.0 to before 7.62.0VulnerableHaxx
cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:*14.04VulnerableCanonical
cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:*16.04VulnerableCanonical
cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:*18.04VulnerableCanonical
cpe:2.3:o:canonical:ubuntu_linux:18.10:*:*:*:*:*:*:*18.10VulnerableCanonical
  • cpe:2.3:a:haxx:curl:*:*:*:*:*:*:*:* Versions 7.59.0 to before 7.62.0 Vulnerable ·Haxx
  • cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:* Versions 14.04 Vulnerable ·Canonical
  • cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:* Versions 16.04 Vulnerable ·Canonical
  • cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:* Versions 18.04 Vulnerable ·Canonical
  • cpe:2.3:o:canonical:ubuntu_linux:18.10:*:*:*:*:*:*:* Versions 18.10 Vulnerable ·Canonical

Remediation

Red Hat 1 advisory

  • RHSA-2019:1543 Released 2019-06-18 · Red Hat rating Important
    Red Hat JBoss Core Services Apache HTTP Server 2.4.29 SP2 security update
    • JBoss Core Services Apache HTTP Server 2.4.29 SP2

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat JBoss Core ServicesAffectedNo fix yet
Red Hat Software CollectionsAffectedNo fix yet: Fix deferred
JBoss Core Services Apache HTTP Server 2.4.29 SP2Fixed RHSA-2019:1543
Not affected: 8 products
  • .NET Core 1.0 on Red Hat Enterprise Linux
  • .NET Core 1.1 on Red Hat Enterprise Linux
  • .NET Core 2.1 on Red Hat Enterprise Linux
  • Red Hat Enterprise Linux 5
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8
  • Red Hat JBoss Web Server 5

Timeline

  1. 2026-10-02 Threatist record created from CVE-2018-16840
  2. 2026-10-03 Alias added: GHSA-6vwf-m72q-cw8h

References

Patch 2

Advisory 3

  • 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-2016-07084 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
See all 17 →

Sources

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