How severe is CVE-2018-15501?

CVE-2018-15501 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-2018-15501 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-2018-15501?

CVE-2018-15501 primarily affects Libgit2. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-15501?

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-2018-15501 published?

CVE-2018-15501 was published on 2018-08-18 and last updated on 2026-06-17.

CVE-2018-15501

CVE-2018-15501 is a high-severity vulnerability in Libgit2 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-125.

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-125
Affected product: Libgit2
Published: 2018-08-18
Last modified: 2026-06-17

Description

In ng_pkt in transports/smart_pkt.c in libgit2 before 0.26.6 and 0.27.x before 0.27.4, a remote attacker can send a crafted smart-protocol "ng" packet that lacks a '\0' byte to trigger an out-of-bounds read that leads to DoS.

Frequently asked questions

What is CVE-2018-15501?: In ng_pkt in transports/smart_pkt.c in libgit2 before 0.26.6 and 0.27.x before 0.27.4, a remote attacker can send a crafted smart-protocol "ng" packet that lacks a '\0' byte to trigger an out-of-bounds read that leads to DoS.
How severe is CVE-2018-15501?: CVE-2018-15501 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-2018-15501 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-2018-15501?: CVE-2018-15501 primarily affects Libgit2. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-15501?: 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-2018-15501 published?: CVE-2018-15501 was published on 2018-08-18 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
cpe:2.3:a:libgit2:libgit2:*:*:*:*:*:*:*:*

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