NVD / CVE Program· CNA mitre

CVE-2018-20549: There is an illegal WRITE memory access at caca/file.c (function caca_file_read) in libcaca 0.99.beta19.

Noroxi assessment

Priority: Monitor (action score 36/100)

The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
Probability of exploitation in the next 30 days: 1.8% (FIRST EPSS); higher than 78.9% of all records.
Anyone who can reach it over the internet can trigger it. No account or password is required. A user must open a link or visit a page. No special conditions are required; it is repeatable.
Fixed version: libcaca (Alpine:v3.10) 0.99_beta19-r3; libcaca (Debian:12) 0.99.beta19-2.1; libcaca (Debian:8) 0.99.beta19-2+deb8u1.

Low priority for now. Upgrade to libcaca (Alpine:v3.10) 0.99_beta19-r3; libcaca (Debian:12) 0.99.beta19-2.1; libcaca (Debian:8) 0.99.beta19-2+deb8u1 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

HighCVSS 8.8 · v3.1—No exploit Fix available

Published: Dec 28, 2018
Updated: Jun 16, 2026
EPSS: 1.8% · 78th percentile
CWE: CWE-119

Report tools

JSON

Action score

Monitor

Low priority for now.

CVSS: 35 / 40 · 8.8 / 10
CISA KEV: 0 / 30 · Not listed
EPSS: 1 / 30 · 1.8%

Get told when this record changes

Not in KEV: no record of exploitation in the wild
No public exploit code on record
A fix has been released

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

Vendor	Product	CPE
libcaca project	libcaca	cpe:2.3:a:libcaca_project:libcaca
canonical	ubuntu linux	cpe:2.3:o:canonical:ubuntu_linux
debian	debian linux	cpe:2.3:o:debian:debian_linux
fedoraproject	fedora	cpe:2.3:o:fedoraproject:fedora
opensuse	leap	cpe:2.3:o:opensuse:leap

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

canonical ubuntu linux12.04
canonical ubuntu linux14.04
canonical ubuntu linux16.04
canonical ubuntu linux18.04
canonical ubuntu linux18.10
debian debian linux8.0
fedoraproject fedora34
fedoraproject fedora35
fedoraproject fedora36
libcaca project libcaca0.99
opensuse leap15.0

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

Ecosystem	Package	Affected range	Fix
Alpine:v3.10	libcaca	before 0.99_beta19-r3	0.99_beta19-r3
Debian:12	libcaca	before 0.99.beta19-2.1	0.99.beta19-2.1
Debian:8	libcaca	before 0.99.beta19-2+deb8u1	0.99.beta19-2+deb8u1
openSUSE:Leap 15.0	libcaca	before 0.99.beta19.git20171003-lp150.2.3.1	0.99.beta19.git20171003-lp150.2.3.1
openSUSE:Tumbleweed	libcaca	before 0.99.beta19.git20171003-8.3	0.99.beta19.git20171003-8.3
SUSE:Linux Enterprise Desktop 12 SP4	libcaca	before 0.99.beta18-14.3.27	0.99.beta18-14.3.27
SUSE:Linux Enterprise Module for Server Applications 15	libcaca	before 0.99.beta19.git20171003-3.3.7	0.99.beta19.git20171003-3.3.7

Same product

libcaca project: all records

Other highest-scoring records for the same primary product.

CVE-2018-20548There is an illegal WRITE memory access at common-image.c (function load_image) in libcaca 0.99.beta19 for 1bpp data.
36Monitor
CVE-2018-20545There is an illegal WRITE memory access at common-image.c (function load_image) in libcaca 0.99.beta19 for 4bpp data.
36Monitor
CVE-2018-20547There is an illegal READ memory access at caca/dither.c (function get_rgba_default) in libcaca 0.99.beta19 for 24bpp data.
33Monitor

Published before and after this one in the same product

← EarlierCVE-2018-20544Dec 28, 2018 · There is floating point exception at caca/dither.c (function caca_dither_bitmap) in libcaca 0.99.beta19.
27Monitor
← EarlierCVE-2018-20546Dec 28, 2018 · There is an illegal READ memory access at caca/dither.c (function get_rgba_default) in libcaca 0.99.beta19 for the default bpp case.
33Monitor
Later →CVE-2021-3410Feb 23, 2021 · A flaw was found in libcaca v0.99.beta19.
31Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / package	Fixed version	Source
alpine:libcaca	0.99_beta19-r3 · Alpine:v3.10	Package registry (OSV)
debian:libcaca	0.99.beta19-2.1 · Debian:12	Package registry (OSV)
opensuse:libcaca	0.99.beta19.git20171003-lp150.2.3.1 · openSUSE:Leap 15.0	Package registry (OSV)
suse:libcaca	0.99.beta19.git20171003-3.3.7 · SUSE:Linux Enterprise Module for Server Applications 15	Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

Anyone who can reach it over the internet can trigger it.
No account or password is required.
A user must open a link or visit a page.
No special conditions are required; it is repeatable.

If successful

Confidentiality: high · data can be read
Integrity: high · data or configuration can be modified
Availability: high · the service can be disrupted

Attack vector: Network
Attack complexity: Low
Privileges required: None
User interaction: Required
Scope: Unchanged
Confidentiality impact: High
Integrity impact: High
Availability impact: High

Weakness class (CWE)

CWE-119 · Improper Restriction of Operations within the Bounds of a Memory Buffer

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

nvd-primary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

Attack patterns (CAPEC)

ATT&CK techniques

—

Change log

Fix✗ → ✓Sep 28, 2026, 10:47 PM UTC

For records you follow, these changes also arrive as notifications. →

References

lists.opensuse.org/opensuse-security-announce/2019-04/msg00033.html

Show all references (6 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records