Malicious PDF — malware analysis report

Static analysis result for SHA-256 5fe638657ca4e62f…

MALICIOUS

PDF

80.9 KB Created: 2021-09-03 10:43:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 9a493deca33ecd64e77f38ee000b63a7 SHA-1: 71ab6830c36b3bec7a9a53eb672bbfcf001b4d6d SHA-256: 5fe638657ca4e62f398c4bac0455187b61f358aeae4169dc8f7f6470d2b1b9fb
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely involving exploitation or redirection to harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://garglob.ru/uplcv?utm_term=3d+geometry+problems+pdf PDF link annotation
    • https://baxsporthorses.com/userfiles/file/25150867537.pdfIn PDF document text
    • http://ylphs.com/ckfinder/userfiles/files/17137386128.pdfIn PDF document text
    • https://gamletaarnhuset.no/wp-content/plugins/formcraft/file-upload/server/content/files/160f88360aaf17---99485110520.pdfIn PDF document text
    • http://rkmaster.ru/uploads/files/85004985454.pdfIn PDF document text
    • http://studiomilano.eu/userfiles/files/tefabevoxovogababepunetig.pdfIn PDF document text
    • http://dialog-seversk.ru/jsplugins/ckfinder/userfiles/files/83226895775.pdfIn PDF document text
    • http://qtjdb.com/UploadFile/2021/06/01/file/20210601_041931_160.pdfIn PDF document text
    • http://mesotects.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7657568f2b---rudob.pdfIn PDF document text
    • https://suhrsmad.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16098bac83ec57---83585975927.pdfIn PDF document text
    • https://drahmetbostanci.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082c8025e569---lizovozegidopixuwone.pdfIn PDF document text
    • https://menu2uplus.com/images/file/bejedewerovivilasagez.pdfIn PDF document text
    • https://dehayemek.net/upload/ckfinder/files/3673144833.pdfIn PDF document text
    • https://btegypt.com/file/warijovinesilu.pdfIn PDF document text
    • http://cl-pub.com/files/files/7160097675.pdfIn PDF document text
    • http://pulsrmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160add68b808de---godadewib.pdfIn PDF document text
    • https://securitegenerale.tn/userfiles/file/4316465912.pdfIn PDF document text
    • http://www.photobreak.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609ab3c452b50---pitonukixozejarebe.pdfIn PDF document text
    • http://macautemple.com/userfiles/file/42277047108.pdfIn PDF document text
    • http://aldo-ins.com/userfiles/file/besine.pdfIn PDF document text
    • https://homini.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1609875660b87a---nilorakumakogavupavewe.pdfIn PDF document text
    • https://agenciaboom.com/wp-content/plugins/super-forms/uploads/php/files/k9p4vtidnmlasqng6dp7sb36b6/tugufewigusufomotokerur.pdfIn PDF document text
    • https://siphouse96.com/wp-content/plugins/super-forms/uploads/php/files/94774c8001dd3bf7954944aede7d3ecc/pulipuvitesakuzixatofetad.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_off0000d62d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD62D 18316 bytes
SHA-256: cbcb1b768ffbac990e02cc0dfae7cf861bc88624c21c9a61847fe00e92af89ba
font_01_sfnt_off000105d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105D8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011def.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DEF 10812 bytes
SHA-256: 343790eec62f91529d7984125107e7c5e5ab66374d77e7634a377cc516088074