How severe is CVE-2016-9939?

CVE-2016-9939 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2016-9939 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (90th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2016-9939?

CVE-2016-9939 primarily affects Cryptopp Crypto++. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2016-9939?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2016-9939 published?

CVE-2016-9939 was published on 2017-01-30 and last updated on 2026-06-17.

CVE-2016-9939

CVE-2016-9939 is a high-severity vulnerability in Cryptopp Crypto++ with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 4% (90th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Cryptopp Crypto++
Published: 2017-01-30
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is 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.
How severe is CVE-2016-9939?: CVE-2016-9939 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2016-9939 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (90th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-9939?: CVE-2016-9939 primarily affects Cryptopp Crypto++. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2016-9939?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2016-9939 published?: CVE-2016-9939 was published on 2017-01-30 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:cryptopp:crypto\+\+:5.6.4:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*

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