How severe is CVE-2016-8860?

CVE-2016-8860 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-2016-8860 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2016-8860?

CVE-2016-8860 primarily affects Torproject Tor. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2016-8860?

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-2016-8860 published?

CVE-2016-8860 was published on 2017-01-04 and last updated on 2026-06-17.

CVE-2016-8860

CVE-2016-8860 is a high-severity vulnerability in Torproject Tor 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-119.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 2% (78th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-119
Affected product: Torproject Tor
Published: 2017-01-04
Last modified: 2026-06-17

Description

Tor before 0.2.8.9 and 0.2.9.x before 0.2.9.4-alpha had internal functions that were entitled to expect that buf_t data had NUL termination, but the implementation of or/buffers.c did not ensure that NUL termination was present, which allows remote attackers to cause a denial of service (client, hidden service, relay, or authority crash) via crafted data.

Frequently asked questions

What is CVE-2016-8860?: Tor before 0.2.8.9 and 0.2.9.x before 0.2.9.4-alpha had internal functions that were entitled to expect that buf_t data had NUL termination, but the implementation of or/buffers.c did not ensure that NUL termination was present, which allows remote attackers to cause a denial of service (client, hidden service, relay, or authority crash) via crafted data.
How severe is CVE-2016-8860?: CVE-2016-8860 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-2016-8860 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-8860?: CVE-2016-8860 primarily affects Torproject Tor. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2016-8860?: 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-2016-8860 published?: CVE-2016-8860 was published on 2017-01-04 and last updated on 2026-06-17.

References

Affected products (5)

cpe:2.3:a:torproject:tor:*:*:*:*:*:*:*:*
cpe:2.3:a:torproject:tor:0.2.9.0:alpha:*:*:*:*:*:*
cpe:2.3:a:torproject:tor:0.2.9.1:alpha:*:*:*:*:*:*
cpe:2.3:a:torproject:tor:0.2.9.2:alpha:*:*:*:*:*:*
cpe:2.3:a:torproject:tor:0.2.9.3:alpha:*:*:*:*:*:*

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