Malicious PDF — malware analysis report

Static analysis result for SHA-256 5751ffc6a482e2d8…

MALICIOUS

PDF

71.5 KB Created: 2021-09-30 13:21:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: b485659e9c8c114c5c69daca7f1fb135 SHA-1: b64cb6c088c5d7f3ca84310e740103757484d6ef SHA-256: 5751ffc6a482e2d8cce2c66f5928ff04a7b424db5ec3fe48d0c65c7cbc643bfe
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external links, including those pointing to compromised CMS uploads and link farms on disposable hosting, suggesting a phishing or malware distribution scheme. The PDF structure and embedded URLs are consistent with techniques used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://allytemp.ru/uplcv?utm_term=manufacturing+processes+for+engineering+materials+5th+edition+pdf+free+download PDF link annotation
    • https://noddy.nu/images/file/panekef.pdfIn PDF document text
    • http://duepassidalcentro.it/userfiles/files/betebuvojirusavebi.pdfIn PDF document text
    • https://driftwoodcc.com/userfiles/files/99001178900.pdfIn PDF document text
    • https://wonwon.taipei/photo/file/16480826540.pdfIn PDF document text
    • http://gzperson.com/uploadfile/files/9268697083.pdfIn PDF document text
    • http://www.pointcookelectrician.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16139edf19fd2b---85782470310.pdfIn PDF document text
    • https://studiopros.com/userfiles/file/In PDF document text
    • https://austarpharma.austarchina.com/upload/files/bagutatiralibovoxej.pdfIn PDF document text
    • http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614676409f8ce---vusanamusexefepabadesobed.pdfIn PDF document text
    • http://tfh-filter.hu/_user/file/tatev.pdfIn PDF document text
    • http://www.nanodrywash.com/wp-content/plugins/formcraft/file-upload/server/content/files/161419b8f61182---27968767259.pdfIn PDF document text
    • https://membermimpi.com/contents/files/73552506879.pdfIn PDF document text
    • http://drivescuolaguida.it/userfiles/files/dinokavokale.pdfIn PDF document text
    • http://www.icareonline.net.au/ckfinder/icare/files/gobilotariwurumobi.pdfIn PDF document text
    • https://szalkasszorutacskok.hu/app/webroot/files/content/files/rititilido.pdfIn PDF document text
    • https://gitedu.in/ckfinder/userfiles/files/gidodatolibug.pdfIn PDF document text
    • https://floridainvestment.cz/files/file/zezofubizesowuxiwedaz.pdfIn PDF document text
    • https://www.kadinlarsitesi.org/wp-content/plugins/formcraft/file-upload/server/content/files/161354b9100f41---69735898180.pdfIn PDF document text
    • http://polimak.pl/userfiles/file/saduwib.pdfIn PDF document text
    • http://colorsoftexas.com/ckfinder/userfiles/uploads/kafemiziwigegupofar.pdfIn PDF document text
    • http://pantanalmsnews.com.br/ckfinder/userfiles/files/zufedazurogomoz.pdfIn PDF document text
    • https://khanikango.in/file/xugowafis.pdfIn PDF document text
    • http://fs-select.com/images/blog/file/tanemubujobozoworibewi.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_off0000b3ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3CE 11380 bytes
SHA-256: 371e16fa72bc7681cc67c410d15d34a66c78f86355df059481a1f8921f029f3f
font_01_sfnt_off0000ce53.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE53 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e665.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE665 16000 bytes
SHA-256: 8cff1656aaa3769551398cd34e9164f05afe475f370884b85dd59e2bbbf12be1