Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4ff71eac038b945…

MALICIOUS

PDF

74.3 KB Created: 2021-09-10 01:05:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: db9857059c9793f57fa793b554b4cff5 SHA-1: 380a72ef4730a4736cf0cf6c2f337e904265ac3a SHA-256: f4ff71eac038b9451e106a2e3b2a5e2b08c922cf1d522f4d44d7e19df2433168
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a large number of embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm. The ML classifier strongly flagged this PDF as malicious. The primary purpose appears to be redirecting users to external sites, potentially for SEO manipulation or to serve further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

Heuristics 5

  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://coretry.ru/uplcv?utm_term=simcity+300+cheats PDF link annotation
    • http://toeicspeaking.net/_UploadFile/Images/file/losesusirujufagipopew.pdfIn PDF document text
    • http://firewaterdamagedfw.com/test/fckeditor/uploadfiles/file/60369031748.pdfIn PDF document text
    • https://lanegarrett.net/userfiles/file/vukonelazekagimubelag.pdfIn PDF document text
    • http://chamdure.com/DATA/files/27135381205.pdfIn PDF document text
    • https://newshieldinsurance.com/demo/gsa/final/images/file/wiwizaworinegiwigexop.pdfIn PDF document text
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135a8bf1973e---57822979200.pdfIn PDF document text
    • https://speakingparrot.com/upload/ckfinder/files/42484514644.pdfIn PDF document text
    • https://dunakanyarfesto.hu/ckfinder/userfiles/files/98655928183.pdfIn PDF document text
    • http://ippinnudon.com/uploads/files/dakinakisavoxada.pdfIn PDF document text
    • http://mspchicagolaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/zodamulitawexiguno.pdfIn PDF document text
    • https://chief-moving.com/editor_upload/file/nuzexebafojatemi.pdfIn PDF document text
    • https://salwangurugram.com/files/ziwusesawobegaworifig.pdfIn PDF document text
    • https://mallarpurnaisuva.org/go/file/fonuwelitewakevizasosonoz.pdfIn PDF document text
    • https://tongdaidoanhnghiep.com/app/webroot/upload/files/7064607425.pdfIn PDF document text
    • http://artiguardia.pl/userfiles/file/27374617979.pdfIn PDF document text
    • http://daehwa.info/uploaded/file/35684271767.pdfIn PDF document text
    • https://dacoma.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613743814525a---gabetunojalatewipixane.pdfIn PDF document text
    • https://www.coconutlodge.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a80c99ec00---joxoferowitobufivif.pdfIn PDF document text
    • http://zoekidsworld.com/userfiles/file/82990064212.pdfIn PDF document text
    • http://orderkai.com/uploads/files/88171746710.pdfIn PDF document text
    • https://delaneyllc.com/ckfinder/userfiles/files/51094264591.pdfIn PDF document text
    • https://matricula.netlandschool.cl/files/sodomazorujexusavufotuza.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000bde8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBDE8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d5fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5FA 17748 bytes
SHA-256: 329d780700565dcbbfb9df66453fc7275619c07d15b25dd5857c6773bb75a1d8
font_02_sfnt_off000103d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103D8 10608 bytes
SHA-256: f092324dbf4a0e262742f15c243b7ef259e9b164c010092e3b9c244a15fd13a6