CVE-2015-8659

The idle stream handling in nghttp2 before 1.6.0 allows attackers to have unspecified impact via unknown vectors, aka a heap-use-after-free bug.

Published: 2016-01-12 Last update: 2026-05-06 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2015-8659 is rated High Risk (73.2/100): CVSS Critical severity, with medium exploitation likelihood (EPSS 4.07%). EPSS rose +1.89% over the last day, indicating growing attacker interest. High exploitation likelihood—assess exposure and prioritize remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2015-8659

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 2.19% 4.07% +1.89%
2 2026-03-04 2.31% 2.19% -0.13%
3 2026-03-01 — 2.31% —

Full EPSS history (38 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2015-8659

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
10.0 3.0 CRITICAL
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 6.0 [email protected]
10.0 2.0 HIGH
AV:N/AC:L/Au:N/C:C/I:C/A:C Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:C)
Complete confidentiality impact.
Integrity impact (I:C)
Complete integrity impact.
Availability impact (A:C)
Complete availability impact.
 10.0 10.0 [email protected]

Weakness enumeration for CVE-2015-8659

OS Trackers for CVE-2015-8659

vendor priority summary link
debian not yet assigned CVE-2015-8659 not yet assigned priority: Debian including 1 source packages (nghttp2), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2015-8659
gentoo normal CVE-2015-8659: 1 GLSA(s) (201612-06), 1 atom(s) (net-libs/nghttp2); latest impact normal. https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2015-8659
ubuntu medium CVE-2015-8659 medium priority: Ubuntu including 1 source packages (nghttp2), 9 status rows across 9 suites (artful, precise, trusty, upstream, vivid, wily, xenial, yakkety, zesty): ignored 3, not-affected 3, DNE 2, released 1. https://ubuntu.com/security/CVE-2015-8659

Affected software / configurations for CVE-2015-8659

Vendor Product Version Raw CPE
apple mac_os_x <= 10.11.3 cpe:2.3:o:apple:mac_os_x:*:*:*:*:*:*:*:*
nghttp2 nghttp2 <= 1.5.0 cpe:2.3:a:nghttp2:nghttp2:*:*:*:*:*:*:*:*
apple iphone_os <= 9.2.1 cpe:2.3:o:apple:iphone_os:*:*:*:*:*:*:*:*
apple tvos <= 9.1 cpe:2.3:o:apple:tvos:*:*:*:*:*:*:*:*
apple watchos <= 2.1 cpe:2.3:o:apple:watchos:*:*:*:*:*:*:*:*

References for CVE-2015-8659

URL Tags
http://lists.apple.com/archives/security-announce/2016/Mar/msg00000.html
http://lists.apple.com/archives/security-announce/2016/Mar/msg00001.html
http://lists.apple.com/archives/security-announce/2016/Mar/msg00002.html
http://lists.apple.com/archives/security-announce/2016/Mar/msg00004.html
http://lists.fedoraproject.org/pipermail/package-announce/2016-January/175085.html
http://lists.fedoraproject.org/pipermail/package-announce/2016-January/175423.html
http://www.openwall.com/lists/oss-security/2015/12/23/10
http://www.openwall.com/lists/oss-security/2015/12/23/6
http://www.securitytracker.com/id/1035353
https://nghttp2.org/blog/2015/12/23/nghttp2-v1-6-0/ Patch Vendor Advisory
https://security.gentoo.org/glsa/201612-06
https://support.apple.com/HT206166 Vendor Advisory
https://support.apple.com/HT206167 Vendor Advisory
https://support.apple.com/HT206168 Vendor Advisory
https://support.apple.com/HT206169 Vendor Advisory
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