CVE-2018-16840
9.8
CRITICAL · CVSS 3.1 · EPSS 3.4% (pctl 89)
In your normal cycle
Critical by CVSS (9.8), but no sign of active exploitation.
Description
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.
Scoring
| CVSS | 9.8 (CRITICAL, v3.1) |
|---|---|
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| EPSS | 3.4% — more likely to be exploited than 89% of all CVEs |
| Weakness | CWE-416 |
| On CISA KEV | no |
| Public exploit | none known |
| Published | 2018-10-31 |
| Last modified | 2026-06-17 |
Affected (2)
| Vendor | Product |
|---|---|
| canonical | ubuntu linux |
| haxx | curl |
References
- http://www.securitytracker.com/id/1042013
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-16840
- https://curl.haxx.se/docs/CVE-2018-16840.html
- https://github.com/curl/curl/commit/81d135d67155c5295b1033679c606165d4e28f3f
- https://security.gentoo.org/glsa/201903-03
- https://usn.ubuntu.com/3805-1/
- http://www.securitytracker.com/id/1042013
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-16840
- https://curl.haxx.se/docs/CVE-2018-16840.html
- https://github.com/curl/curl/commit/81d135d67155c5295b1033679c606165d4e28f3f
- https://security.gentoo.org/glsa/201903-03
- https://usn.ubuntu.com/3805-1/
→ the Explorer · watch your stack · NVD