CVE-2016-9939

Crypto++ (aka cryptopp and libcrypto++) 5.6.4 contained a bug in its ASN.1 BER decoding routine. The library will allocate a memory block based on the length field of the ASN.1 object. If there is not enough content octets in the ASN.1 object, then the function will fail and the memory block will be zeroed even if its unused. There is a noticeable delay during the wipe for a large allocation.

Published: 2017-01-30 Last update: 2026-05-13 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2016-9939 is rated Moderate Risk (59.7/100): CVSS High severity, with medium exploitation likelihood (EPSS 4.20%). Review affected assets and schedule 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-2016-9939

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 5.92% 4.20% -1.72%
2 2025-03-30 26.45% 5.92% -20.54%
3 2025-03-29 — 26.45% —

Full EPSS history (7 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2016-9939

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.0 HIGH
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 [email protected]
5.0 2.0 MEDIUM
AV:N/AC:L/Au:N/C:N/I:N/A:P 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:N)
No confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:P)
Partial availability impact.
 10.0 2.9 [email protected]

Weakness enumeration for CVE-2016-9939

OS Trackers for CVE-2016-9939

vendor priority summary link
debian not yet assigned CVE-2016-9939 not yet assigned priority: Debian including 1 source packages (libcrypto++), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2016-9939
ubuntu low CVE-2016-9939 low priority: Ubuntu including 1 source packages (libcrypto++), 8 status rows across 8 suites (artful, bionic, precise, trusty, upstream, xenial, yakkety, zesty): not-affected 3, released 3, ignored 2. https://ubuntu.com/security/CVE-2016-9939

Affected software / configurations for CVE-2016-9939

Vendor Product Version Raw CPE
cryptopp crypto\+\+ 5.6.4 cpe:2.3:a:cryptopp:crypto\+\+:5.6.4:*:*:*:*:*:*:*
debian debian_linux 8.0 cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*

References for CVE-2016-9939

cvelogic Threat Intelligence