Security readout for executives and security teams
CVE-2018-16840 is a memory safety bug in curl/libcurl. Affected versions can write to memory after it has already been freed while cleaning up an easy handle. The published severity is medium, with limited integrity impact and required user interaction. Treat it as a patching and inventory issue, not an emergency absent evidence of exploitation. Exposure is most likely where curl or libcurl 7.59.0 through 7.61.1 is installed, packaged, or embedded. Applications statically linked to affected libcurl versions may remain exposed even after OS package updates. Actual risk depends on whether the vulnerable cleanup path is reachable in deployed software. Schedule remediation through normal vulnerability management with attention to embedded and statically linked dependencies. Escalate priority if affected curl/libcurl is present in internet-facing, high-volume, or security-sensitive workflows, but the source bundle does not justify emergency handling. Mitigation focus: Upgrade curl/libcurl to a vendor-supported fixed version outside 7.59.0 through 7.61.1.; Apply relevant operating-system vendor updates from Ubuntu, Gentoo, Red Hat, or your distribution vendor.; Rebuild and redeploy applications that statically link libcurl..
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
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ATT&CK lookup starting points
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CWE-416: Exact CWE lookup
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Open ATT&CK lookupCVE-2018-16840 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 4.3 (3.0)
- Known Exploited
- No
- Published
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N2.81.4Primary CVE scoreVulnerability scoring details
Base CVSS 3.0 score
4.3MediumVector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
Source materials
- CVE List V5 sourceCVE List V5
- GLSA-201903-03CVE reference · vendor-advisory, x_refsource_GENTOO
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-16840CVE reference · x_refsource_CONFIRM
- https://github.com/curl/curl/commit/81d135d67155c5295b1033679c606165d4e28f3fCVE reference · x_refsource_CONFIRM
- https://curl.haxx.se/docs/CVE-2018-16840.htmlCVE reference · x_refsource_MISC
- USN-3805-1CVE reference · vendor-advisory, x_refsource_UBUNTU
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Use After Free
Use After Free represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.