An issue was discovered in libxls before and including 1.6.1 when reading Microsoft Excel files.

published 2021-02-23 5 y ago modified 2026-08-13 2 mo ago also EUVD-2020-20320 , JLSEC-2026-1294

cvss: 5.5; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 0.8%; EPSS 0.8% chance of exploitation in 30 days, percentile 57%
public exploits: 0; none known

An issue was discovered in libxls before and including 1.6.1 when reading Microsoft Excel files. A NULL pointer dereference vulnerability exists when parsing XLS cells in libxls/xls2csv.c:199. It could allow a remote attacker to cause a denial of service via crafted XLS file.

Patch / fix

fixed in 2 distros 1

julia libxls_jll 1.6.2+0
libxls_project libxls 1.6.2

libxls openSUSE Leap 15.2 1.6.2-lp152.2.3.1

opensuse advisories openSUSE-SU-2021:0812-1

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2020-27819 updated 2025-11-21 cvss 7.5

libxls: NULL pointer dereference via crafted xls file

Red Hat All currently supported Red Hat products
not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

0.83% chance of exploitation in the next 30 days, higher than 57% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
NVD	3.1	5.5	CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
NVD	2.0	4.3	AV:N/AC:M/Au:N/C:N/I:N/A:P
OSV	3.1	5.5	CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

Affected packages

ecosystem	package	affected	fixed in
julia	libxls_jll	<1.6.2+0	1.6.2+0

Affected products

n/a libxls

Classification

Weakness

CWE-476 NULL Pointer Dereference

References

bugzilla.redhat.com /show_bug.cgi?id=1903296
issue-tracking, third-party-advisory, web

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary