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CVE Record

CVE-2018-5521: On F5 BIG-IP 12.1.0-12.1.3.1, 11.6.1-11.6.3.1, 11.5.1-11.5.5, or 11.2.1, carefully crafted URLs can be used...

On F5 BIG-IP 12.1.0-12.1.3.1, 11.6.1-11.6.3.1, 11.5.1-11.5.5, or 11.2.1, carefully crafted URLs can be used to reflect arbitrary content into GeoIP lookup responses, potentially exposing clients to XSS.

UnknownCVSS not scoredNot KEV-listedUpdated
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Glexia's TakeAutomated analysis

Security readout for executives and security teams

CVE-2018-5521 affects several older F5 BIG-IP versions. A specially formed URL can cause arbitrary content to be reflected in GeoIP lookup responses, creating a potential cross-site scripting risk for clients that receive those responses. Exposure is likely limited to organizations still running the specified older BIG-IP versions and using affected GeoIP lookup response paths reachable by untrusted clients. Treat this as a targeted legacy-platform risk. Prioritize if affected BIG-IP systems remain internet-facing or serve untrusted clients, but avoid emergency assumptions without vendor scoring or exploitation evidence. Mitigation focus: Check F5 advisory K23124150 for vendor-confirmed fixed versions and guidance.; Upgrade or patch affected BIG-IP systems according to F5 guidance.; Reduce untrusted reachability to affected GeoIP lookup functionality where operationally feasible..

Prepared

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

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CVE-2018-5521 mapping review

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Vulnerability profileCVE Program record
Severity
Unknown
CVSS
Not scored
Known Exploited
No
Published
Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

0CVSS vectors
0Timeline events
0ADP providers
2Source links

CVSS and timeline data

No CVSS vectors or timeline events were available in the normalized CVE source material.

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
F5 Networks, Inc.BIG-IP (LTM, AAM, AFM, Analytics, APM, ASM, DNS, Edge Gateway, FPS, GTM, Link Controller, PEM, WebAccelerator)12.1.0-12.1.3.1, 11.6.1-11.6.3.1, 11.5.1-11.5.5, 11.2.1Listed
Weakness

CWE details

No CWE listed

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