Security readout for executives and security teams
Plain-English summary
CVE-2016-8623 is a low-severity curl cookie-handling flaw. In affected versions before 7.51.0, another thread could trigger a use-after-free condition that may expose limited information. It requires local access and privileges, so business urgency is generally low unless legacy curl is embedded in sensitive systems.
Executive priority
Treat as routine remediation. The issue can disclose limited information, but the supplied evidence points to local, privileged exploitation conditions and no known active exploitation signal.
Technical view
The flaw is CWE-416 use-after-free in curl cookie handling before version 7.51.0. The CVSS 3.0 vector is local, low complexity, low privileges, no user interaction, unchanged scope, and low confidentiality impact only. Integrity and availability impacts are not indicated in the supplied sources.
Likely exposure
Exposure is most likely in legacy hosts, containers, appliances, or applications still shipping curl versions before 7.51.0. Internet-facing exposure is not indicated by the provided CVSS vector because exploitation is local and requires privileges.
Exploitation context
The source bundle does not show CISA KEV listing or other cited evidence of active exploitation. Practical risk depends on whether an attacker already has local privileged access to a system using the vulnerable curl cookie code.
Researcher notes
Focus analysis on threaded cookie handling and fixed curl lineage. The supplied sources identify the issue class and patch availability but do not provide evidence of remote exploitation, integrity impact, or availability impact.
Mitigation direction
- Upgrade curl to version 7.51.0 or a vendor-fixed package.
- Apply relevant Red Hat, Gentoo, Oracle, or other vendor advisories for packaged curl.
- Check embedded application and container images for bundled vulnerable curl builds.
- Prioritize remediation on multi-user systems and sensitive workloads.
- If upgrade is delayed, follow current vendor guidance for compensating controls.
Validation and detection
- Inventory curl versions across hosts, images, and application bundles.
- Confirm packaged curl includes vendor fixes for CVE-2016-8623.
- Review vulnerability scanner results against vendor advisories, not only upstream version strings.
- Verify sensitive systems no longer run curl versions before 7.51.0.
- Track exceptions where appliances or third-party products bundle their own curl.
Public sources used
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
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-416: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2016-8623 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
- Low
- CVSS
- 3.3 (3.0)
- Known Exploited
- No
- Published
Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/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:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N1.81.4Primary CVE scoreVulnerability scoring details
Base CVSS 3.0 score
3.3LowVector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
Source materials
- CVE List V5 sourceCVE List V5
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2016-8623CVE reference · x_refsource_CONFIRM
- RHSA-2018:3558CVE reference · vendor-advisory, x_refsource_REDHAT
- https://curl.haxx.se/docs/adv_20161102I.htmlCVE reference · x_refsource_CONFIRM
- https://www.tenable.com/security/tns-2016-21CVE reference · x_refsource_CONFIRM
- https://curl.haxx.se/CVE-2016-8623.patchCVE reference · x_refsource_CONFIRM
- RHSA-2018:2486CVE reference · vendor-advisory, x_refsource_REDHAT
- GLSA-201701-47CVE reference · vendor-advisory, x_refsource_GENTOO
- [bookkeeper-issues] 20210628 [GitHub] [bookkeeper] padma81 opened a new issue #2746: Security Vulnerabilities in CentOS 7 image, Upgrade image to CentOS 8CVE reference · mailing-list, x_refsource_MLIST
- [bookkeeper-issues] 20210629 [GitHub] [bookkeeper] padma81 opened a new issue #2746: Security Vulnerabilities in CentOS 7 image, Upgrade image to CentOS 8CVE reference · mailing-list, x_refsource_MLIST
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.