What is CVE-2018-13843?

CVE-2018-13843 is a high-severity vulnerability in Htslib, classified under Missing Release of Resource after Effective Lifetime. CVSS score: 7.5/10. Published 2018-07-10.

How severe is CVE-2018-13843?

High severity. CVSS v3 base score is 7.5 out of 10.

Is CVE-2018-13843 known to be exploited?

2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Vulnerability in Htslib

CVE-2018-13843

An issue has been found in HTSlib 1.8. It is a memory leak in bgzf_getline in bgzf.c. NOTE: the software maintainer's position is that the "failure to free memory" can be fixed in applications that use the HTSlib library (such as test/test_bgzf.c in the original report) and is not a library issue

Published 2018-07-10 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.015 (72.8th percentile), scored 2026-09-30.

Low probability of exploitation in the next 30 days, but still tracked. 73rd percentile — 72.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.015 · newest: 0.015 · change: 0.000

Affected products

Htslib — versions 1.8

Weakness classification (CWE)

CWE-772 — Missing Release of Resource after Effective Lifetime

Public proof-of-concept exploits

References

github.com/samtools/htslib/issues/731 (Exploit, Patch, Third Party Advisory)

Frequently asked questions

What is CVE-2018-13843?: CVE-2018-13843 is a high-severity vulnerability in Htslib, classified under Missing Release of Resource after Effective Lifetime. CVSS score: 7.5/10. Published 2018-07-10.
How severe is CVE-2018-13843?: High severity. CVSS v3 base score is 7.5 out of 10.
Is CVE-2018-13843 known to be exploited?: 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.