How severe is CVE-2021-1494?

CVE-2021-1494 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-2021-1494 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (61st percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2021-1494?

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

Does CVE-2021-1494 have an EU (EUVD) identifier?

Yes. CVE-2021-1494 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-6961.

When was CVE-2021-1494 published?

CVE-2021-1494 was published on 2024-11-15 and last updated on 2026-06-17.

CVE-2021-1494

CVE-2021-1494 is a medium-severity vulnerability 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-693.

Key facts

Severity: Medium (CVSS 3.x base score 5.8)
EPSS exploit prediction: 1% (61st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2021-6961
Weakness: CWE-693
Published: 2024-11-15
Last modified: 2026-06-17

Description

Multiple Cisco products are affected by a vulnerability in the Snort detection engine that could allow an unauthenticated, remote attacker to bypass a configured file policy for HTTP. The vulnerability is due to incorrect handling of specific HTTP header parameters. An attacker could exploit this vulnerability by sending crafted HTTP packets through an affected device. A successful exploit could allow the attacker to bypass a configured file policy for HTTP packets and deliver a malicious payload.

Frequently asked questions

What is CVE-2021-1494?: Multiple Cisco products are affected by a vulnerability in the Snort detection engine that could allow an unauthenticated, remote attacker to bypass a configured file policy for HTTP. The vulnerability is due to incorrect handling of specific HTTP header parameters. An attacker could exploit this vulnerability by sending crafted HTTP packets through an affected device. A successful exploit could allow the attacker to bypass a configured file policy for HTTP packets and deliver a malicious payload.
How severe is CVE-2021-1494?: CVE-2021-1494 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-2021-1494 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (61st percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2021-1494?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2021-1494 have an EU (EUVD) identifier?: Yes. CVE-2021-1494 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-6961.
When was CVE-2021-1494 published?: CVE-2021-1494 was published on 2024-11-15 and last updated on 2026-06-17.

References

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-http-fp-bp-KfDdcQhc

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