NVD / CVE Program· CNA cisco

CVE-2026-20348: ClamAV XAR File Format Processing Memory Corruption Vulnerability

HighCVSS 7.5 · v3.1—No exploit Fix available

Noroxi assessment

Priority: Monitor (action score 30/100)

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: 0.71% (FIRST EPSS); higher than 54.3% of all records.
Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
According to CISA the attack is automatable: targets can be found by mass scanning.
Fixed version: azl3 clamav 1.5.3-1 on Azure Linux 3.0 1.5.4-1.

Low priority for now. Upgrade to azl3 clamav 1.5.3-1 on Azure Linux 3.0 1.5.4-1 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

A vulnerability in the XAR file format parser of ClamAV could allow an unauthenticated, remote attacker to cause a DoS condition or possibly other expanded impacts as a result of memory corruption on an affected device. This vulnerability is due to improper boundary checks for content in XAR files during scanning. An attacker could exploit this vulnerability by submitting a crafted file that contains XAR content to be scanned by ClamAV on an affected device. A successful exploit could allow the attacker to cause the ClamAV scanning process to terminate, resulting in a DoS condition on the affected software.

Published: Aug 7, 2026
Updated: Oct 23, 2026
EPSS: 0.7% · 54th percentile
CWE: CWE-120

Report tools

JSON

Action score

Monitor

Low priority for now.

CVSS: 30 / 40 · 7.5 / 10
CISA KEV: 0 / 30 · Not listed
EPSS: 0 / 30 · 0.7%

CISA SSVC decision

Exploitation: none
Automatable: yes
Technical impact: partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD: —
CNA · cisco: 7.5; NVD has not scored this yet; the score shown is the CNA’s.

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

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

If any of these changes, we'll tell you in the daily email digest.

Is your version affected? Check it

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
cisco	secure endpoint	cpe:2.3:a:cisco:secure_endpoint

Versions reported by the vendor

Affected version ranges reported by the assigning authority (cisco). Independent of NVD's CPE analysis and usually ahead of it.

Cisco Cisco Secure Endpoint
- 7.0.5, 6.2.19, 7.3.3, 7.2.13, 6.1.5, 6.3.1, 6.2.5, 7.3.5, 6.2.1, 7.2.7, 7.1.1, 6.3.5 … (+28)affected

Affected versions · NVD (4)

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

cisco secure endpointbefore 1.27.4
cisco secure endpointbefore 1.29.2
cisco secure endpointbefore 7.5.24.21780
cisco secure endpoint8.0.0 and later · before 8.6.3

Package-level exposure

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

Ecosystem	Package	Affected range	Fix
Alpine:v3.24	clamav	before 1.4.6-r0	1.4.6-r0
Debian:12	clamav	before 1.4.6+dfsg-0+deb12u1	1.4.6+dfsg-0+deb12u1
Debian:13	clamav	from 0	—
Debian:14	clamav	before 1.4.6+dfsg-1	1.4.6+dfsg-1
openSUSE:Leap 16.0	clamav	before 1.5.4-160000.1.1	1.5.4-160000.1.1
openSUSE:Tumbleweed	clamav	before 1.5.4-1.1	1.5.4-1.1
SUSE:Linux Enterprise Micro 5.5	clamav	before 1.5.4-150400.13.11.1	1.5.4-150400.13.11.1
SUSE:Linux Enterprise Module for Basesystem 15 SP7	clamav	before 1.5.4-150600.18.31.1	1.5.4-150600.18.31.1
SUSE:Linux Enterprise Server 12 SP5-LTSS	clamav	before 1.5.4-3.59.1	1.5.4-3.59.1
SUSE:Linux Enterprise Server 16.0	clamav	before 1.5.4-160000.1.1	1.5.4-160000.1.1

Same product

cisco: all records

Other highest-scoring records for the same primary product.

CVE-2024-20290A vulnerability in the OLE2 file format parser of ClamAV could allow an unauthenticated, remote attacker to cause a denial of service (DoS)…
40Plan
CVE-2023-20212A vulnerability in the AutoIt module of ClamAV could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition…
31Monitor
CVE-2023-20197A vulnerability in the filesystem image parser for Hierarchical File System Plus (HFS+) of ClamAV could allow an unauthenticated, remote…
30Monitor

Published before and after this one in the same product

← EarlierCVE-2023-20084Nov 22, 2023 · A vulnerability in the endpoint software of Cisco Secure Endpoint for Windows could allow an authenticated, local attacker to evade…
17Monitor

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
azl3 clamav 1.5.3-1 on Azure Linux 3.0	1.5.4-1 · CBL-Mariner Releases	Microsoft (MSRC)
alpine:clamav	1.4.6-r0 · Alpine:v3.24	Package registry (OSV)
debian:clamav	1.4.6+dfsg-0+deb12u1 · Debian:12	Package registry (OSV)
debian:clamav	1.4.6+dfsg-1 · Debian:14	Package registry (OSV)
opensuse:clamav	1.5.4-1.1 · openSUSE:Tumbleweed	Package registry (OSV)
suse:clamav	1.5.4-160000.1.1 · SUSE:Linux Enterprise Server 16.0	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.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Not on record for this CVE: patch commit or PR link · researcher credit · variant or chain candidate · public bounty program.

Technical details

Attack conditions

Anyone who can reach it over the internet can trigger it.
No account or password is required.
No user action is required.
No special conditions are required; it is repeatable.

If successful

Confidentiality: none
Integrity: none
Availability: high · the service can be disrupted

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

Weakness class (CWE)

CWE-120 · Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

CVSS vector

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

nvd-secondary

Root cause

When data is copied, the source length is not compared with the size of the destination buffer. Excess data overwrites adjacent memory.

The bug in code

The whole CWE-120 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

1char buf[256];
2memcpy(buf, pkt->data, pkt->len);

Fixed

1char buf[256];
2if (pkt->len > sizeof(buf)) {
3  return -EINVAL;
4}
5memcpy(buf, pkt->data, pkt->len);

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 (1)

Fix✗ → ✓Sep 28, 2026, 10:07 PM UTC

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

References

sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-clamav-WuuvVd26

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

All records