CVE-2016-8618: haxx curl Use After Free
Vulnerability summary
CVE-2016-8618 is a critical (CVSS 9.8) Use After Free vulnerability in haxx curl. EPSS estimates a 4.57% chance of exploitation in the next 30 days, higher than 91.6% of scored vulnerabilities.
Not severe (CVSS 5.3, network access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 9 · Related 5Timeline
- 31-07-2018PublishedVulnerability first disclosed.
- 06-08-2024Last modifiedVulnerability information updated.
Description
The libcurl API function called `curl_maprintf()` before version 7.51.0 can be tricked into doing a double-free due to an unsafe `size_t` multiplication, on systems using 32 bit `size_t` variables.
CVSS metrics
6 scores · 5 sources · 2 versions- CVE.orgCNA5.3MediumCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:NDiffers
- OSV · AlpineEcosystem advisory · calculated9.8CriticalCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- OSV · UbuntuEcosystem advisory · calculated5.3MediumCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:NDiffers
- OSV · DebianEcosystem advisory · calculated9.8CriticalCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS trend
Probability
4.57%
Chance of exploitation in the next 30 days
Percentile
92%
Versus all other CVEs
30-day change
Decrease -0.26 pp
From 4.84% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root cause- CWE-416Use After FreeThe product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.
- CWE-415Double FreeThe product calls free() twice on the same memory address.
Affected systems
Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.
Alpine1 product
- curl< 7.51.0-r0 | < 7.51.0 | < 7.49.1-r4
Debian1 product
- curl< 7.51.0-1
Haxx1 product
- curl< 7.51.0
The curl project1 product
- curl7.51.0
Ubuntu1 product
- curl< 7.35.0-1ubuntu2.10 | < 7.47.0-1ubuntu2.2
5 vendors · 5 products
References
14 links- bugzilla.redhat.com/show_bug.cgi?id=CVE-2016-8618X Refsource CONFIRMIssue TrackingPatchThird Party Advisory
- www.oracle.com/technetwork/security-advisory/cpuoct2018-4428296.htmlX Refsource CONFIRM
