Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf896c4b6b1ff086…

MALICIOUS

PDF

87.3 KB Created: 2021-09-08 04:01:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 2a7e2753d35e4e11961d1881df4c8b75 SHA-1: 8e96aed6fbd5b7a15a7cb52130bf7710399f1932 SHA-256: cf896c4b6b1ff08684c693b111628dd5763d40e310fd50a05a88abd092382f4e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF that contains numerous links, many of which point to potentially compromised or disposable hosting sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and heuristic firings suggest it's designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://agatanorek.com/files/file/bukixadopikerunukebitonuf.pdf In PDF document text
    • https://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ffd4af6d948---wosujenonatifadewos.pdfIn PDF document text
    • http://sdds.be/userfiles/file/valupubenifapijilunusako.pdfIn PDF document text
    • http://clearspace-design.com/CKEdit/upload/files/likapexojomemubazerewo.pdfIn PDF document text
    • http://controlsystemco.com/cache/fck_files/file/63364111977.pdfIn PDF document text
    • http://location-appartement-venise.com/italie_documents/files/zipatubexomijusokudepam.pdfIn PDF document text
    • https://gpuhub.net/wp-content/plugins/super-forms/uploads/php/files/a9sa2qu95nuqi2m8n3ugrmnh1a/2420243364.pdfIn PDF document text
    • http://dabaizhongxue.com/upload_fck/file/2021-7-9/20210709091350549941.pdfIn PDF document text
    • http://hasici-pristroje-eshop.cz/files/file/66289071637.pdfIn PDF document text
    • http://sanarina.de/ckfinder/userfiles/files/sirotenowimudonimofipiju.pdfIn PDF document text
    • https://activepymes.com/pub/file/safelopa.pdfIn PDF document text
    • http://xperion.hu/wp-content/plugins/super-forms/uploads/php/files/b369c49b7d0126ea48caf7bf9075b393/15524838316.pdfIn PDF document text
    • https://cahayaapi1.com/contents/files/33715868661.pdfIn PDF document text
    • http://ackerviewguesthouse.com/userfiles/file/55149532079.pdfIn PDF document text
    • http://monkey-do.net/userfiles/file/rojepamudoxisenan.pdfIn PDF document text
    • http://u15.ch/ckfinder/userfiles/files/kibodujaf.pdfIn PDF document text
    • http://bagiez.com/userfiles/file/36616046834.pdfIn PDF document text
    • http://e-kva.ru/admin/ckfinder/userfiles/files/wikexopiwebimavopugisagim.pdfIn PDF document text
    • https://rocksoliddesigns.biz/userfiles/file/11863479496.pdfIn PDF document text
    • https://www.geosuiteonline.de/wp-content/plugins/formcraft/file-upload/server/content/files/160796033ecd36---71958569606.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=basic+english+grammar+book+1+teacher%27s+resource+guide+pdfPDF link annotation
    • 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_off0000ed3b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED3B 11540 bytes
SHA-256: eadd613e2663ba0cc5bc19fbd842f4adc9441e5626aafa1394f0b929092a1bad
font_01_sfnt_off0001080d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1080D 18188 bytes
SHA-256: ac6c7448d15ad8e2b54af1d8007e4770a3d1f88fe3217eafebaf05abb754f176
font_02_sfnt_off00013704.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13704 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1