How severe is CVE-2020-26082?

CVE-2020-26082 has a CVSS 3.x base score of 5.8, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2020-26082 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (46th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-26082?

CVE-2020-26082 affects Cisco Asyncos. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-26082?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2020-26082 published?

CVE-2020-26082 was published on 2023-08-04 and last updated on 2026-06-17.

CVE-2020-26082

CVE-2020-26082 is a medium-severity vulnerability in Cisco Asyncos with a CVSS 3.x base score of 5.8. 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-20.

Key facts

Severity: Medium (CVSS 3.x base score 5.8)
EPSS exploit prediction: 1% (46th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Cisco Asyncos
Published: 2023-08-04
Last modified: 2026-06-17

Description

A vulnerability in the zip decompression engine of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to bypass content filters that are configured on an affected device. The vulnerability is due to improper handling of password-protected zip files. An attacker could exploit this vulnerability by sending a malicious file inside a crafted zip-compressed file to an affected device. A successful exploit could allow the attacker to bypass configured content filters that would normally drop the email.

Frequently asked questions

What is CVE-2020-26082?: A vulnerability in the zip decompression engine of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to bypass content filters that are configured on an affected device. The vulnerability is due to improper handling of password-protected zip files. An attacker could exploit this vulnerability by sending a malicious file inside a crafted zip-compressed file to an affected device. A successful exploit could allow the attacker to bypass configured content filters that would normally drop the email.
How severe is CVE-2020-26082?: CVE-2020-26082 has a CVSS 3.x base score of 5.8, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2020-26082 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (46th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-26082?: CVE-2020-26082 affects Cisco Asyncos. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-26082?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-26082 published?: CVE-2020-26082 was published on 2023-08-04 and last updated on 2026-06-17.

References

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-esa-zip-bypass-gbU4gtTg

Affected products (1)

cpe:2.3:o:cisco:asyncos:*:*:*:*:*:*:*:*

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