Malicious PDF — malware analysis report

Static analysis result for SHA-256 541bde33a877b32c…

MALICIOUS

PDF

91.4 KB Created: 2021-07-21 10:17:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: 3bac519959249392ae854100f2850325 SHA-1: b4042c7663705f03f485174b5a8027df13ec0312 SHA-256: 541bde33a877b32c272a7cd0d3a40c028a461f7c76e58bbaf9277a6961f2d160
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to obscure the ultimate destination. ClamAV and an ML classifier flagged this PDF as malicious, specifically as a phishing trojan. The presence of these link farms and the malware detection strongly suggest an attempt to lure users to malicious content, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9765

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://bnovum.hu/downloads/73928247861.pdf In PDF document text
    • http://jplus-ag.com/upload/files/BodyFile__60ECA78D1D420.pdfIn PDF document text
    • https://cgeminfos.ma/upload/file/regukota.pdfIn PDF document text
    • http://richfield1962.com/clients/4/47/47516dc9824f3897220912ef171c404f/File/61950301808.pdfIn PDF document text
    • http://beiwendq.com/userfiles/file/28751280698.pdfIn PDF document text
    • https://zweiund40.com/wp-content/plugins/super-forms/uploads/php/files/g9v7eurafdofbkg7kl2llc5sjl/50540888529.pdfIn PDF document text
    • http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160831612769b9---95950095553.pdfIn PDF document text
    • http://smithmurdock.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc2e31233c1---98428598700.pdfIn PDF document text
    • https://pilotcenter.gr/wp-content/plugins/super-forms/uploads/php/files/b2pp3c2adbd8pamdnrpbpf3p1v/22358120443.pdfIn PDF document text
    • https://sellos-mecanicos.com/wp-content/plugins/super-forms/uploads/php/files/68b324e4ec99074c3e98cb7e56aadf1e/22885543862.pdfIn PDF document text
    • http://pvhs1967.com/clients/a/aa/aa78cb05297cd93d8a9ab6bd1eb8a3c4/File/kegodipasaxexojap.pdfIn PDF document text
    • https://nowbali.co.id/wp-content/plugins/formcraft/file-upload/server/content/files/1607c62b60fcc5---31254848949.pdfIn PDF document text
    • https://vishalahospitality.com/ckfinder/userfiles/files/88306683221.pdfIn PDF document text
    • https://weeb.nu/userfiles/file/jorumibo.pdfIn PDF document text
    • https://dusunceokulu.net/resimler/files/56614925832.pdfIn PDF document text
    • http://abwingssuffolk1.com/uploads/files/sodifizugudikete.pdfIn PDF document text
    • https://eclipsetheaters.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a36bf3817d6---gibanudeput.pdfIn PDF document text
    • http://www.ih-consultant.com/ckfinder/userfiles/files/15105883383.pdfIn PDF document text
    • https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1606fd6ca55cdc---mepufikilem.pdfIn PDF document text
    • https://mimpishio2.net/contents//files/46998387618.pdfIn PDF document text
    • https://www.alignerco.ca/wp-content/plugins/super-forms/uploads/php/files/14ca3a91fb5760e6f1b4ef5d1d2bf60d/3694997070.pdfIn PDF document text
    • http://acetuitioncentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1609b1f5c8efd9---wefixepeguridef.pdfIn PDF document text
    • https://petroblend.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071ba3a34fbc---42850970133.pdfIn PDF document text
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a47b74469a5---12975614399.pdfIn PDF document text
    • http://cunningham-reunion.com/clients/7/73/7399477c88ef979e1ad3ac38e42cffcc/File/ritilojenemudanifekek.pdfIn PDF document text
    • http://zoop-tech.com/ckfinder/userfiles/files/91489615262.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=whatsapp+blue+tick+off+androidPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e995.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE995 11044 bytes
SHA-256: 0786fdfb2116edd7c16092e7a42846467cdb012381fbce0825580625c5312080
font_01_sfnt_off00010302.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10302 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011b14.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B14 17844 bytes
SHA-256: 7f4b6e02265b101488695a1f1ad8b73a0aaf1b9ec0949fc68cd1e3154d3f91b9
font_03_sfnt_off00014889.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14889 16144 bytes
SHA-256: fcca37035df06e555c2991ff65faa0e8497ca6423bee408ebc46b3aef925b516