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.
CVE-2021-1495
This medium-severity CVE scores 5.8 under NVD CVSS v3. EPSS exploit probability: 1.7%, top 25% of all CVEs by exploit prediction. GitHub Security Advisory enrichment pending alignment with NVD CVSS.
- Lower severity and no public exploit yet
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 5.8
- EG Score
- 5.8(medium)
- EG Risk
- 42(Track)EG Risk 42/100SSVC: Track
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity58% × 45%Exploitation2% × 40%Automatability100% × 15%Action: Routine — remediate on your standard cadence. - EPSS
- 75.0%
- KEV
- Not listed
Published
April 29, 2021
Last Modified
November 21, 2024
References (6)
- psirt@ciscohttps://lists.debian.org/debian-lts-announce/2023/02/msg00011.html
- psirt@ciscohttps://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-http-fp-bp-KfDdcQhc
- psirt@ciscohttps://www.debian.org/security/2023/dsa-5354
- af854a3a-2127-422b-91ae-364da2661108https://lists.debian.org/debian-lts-announce/2023/02/msg00011.html
- af854a3a-2127-422b-91ae-364da2661108https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-http-fp-bp-KfDdcQhc
- af854a3a-2127-422b-91ae-364da2661108https://www.debian.org/security/2023/dsa-5354
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 10× in last 7d / 47× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-07-23 01:56 UTCEG score recompute
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Related CVEs(same CWE)
Same CWE
10 shownCWE-755
- CVE-2009-5043EG 9.8CRITICAL
- CVE-2019-17195EG 9.8EPSS 95%CRITICAL
- CVE-2019-14431EG 9.8CRITICAL
- CVE-2019-12815EG 9.8EPSS 99%CRITICAL
- CVE-2019-6256EG 9.8CRITICAL
- CVE-2018-19991EG 9.8CRITICAL
- CVE-2017-2877EG 9.8CRITICAL
- CVE-2017-5638EG 9.8 KEVEPSS 100%CRITICAL
- CVE-2018-0155NVD 8.6EG 9.0 KEVEPSS 94%HIGH
- CVE-2019-14287EG 8.9EPSS 99%HIGH
Frequently asked(5)
What is CVE-2021-1495?
When was CVE-2021-1495 disclosed?
Is CVE-2021-1495 actively exploited?
What is the CVSS score of CVE-2021-1495?
How do I remediate CVE-2021-1495?
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2021-1495
Is Your Infrastructure Affected by CVE-2021-1495?
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