Malicious PDF — malware analysis report

Static analysis result for SHA-256 5a73178604f5f840…

MALICIOUS

PDF

76.4 KB Created: 2021-09-11 13:07:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 3cc51da9c92781eaba1fca0805f1f2f3 SHA-1: ada241f4ad811b2d1b75e0cae58afac6999f2241 SHA-256: 5a73178604f5f840245c3e50e162d893b51c568ed3582778a511026e534133f8
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 CMS upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of multiple links to potentially compromised sites suggests an attempt to leverage these to host or redirect to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://carmelocuritiba.com.br/ckfinder/userfiles/files/vibosoxizisodalafu.pdf In PDF document text
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16137a83686d43---nujesesawow.pdfIn PDF document text
    • https://humanistbeauty.com/wp-content/plugins/super-forms/uploads/php/files/vrvh44plj3j3qmcpmabim7v87g/87448532629.pdfIn PDF document text
    • http://bluestandard.pl/ckfinder/userfiles/files/2760693703.pdfIn PDF document text
    • https://jocafoto.com/fotos/file/21823854749.pdfIn PDF document text
    • http://classtool.info/upload/files/wolufab.pdfIn PDF document text
    • https://dortmundpools.com/contents/files/84786011444.pdfIn PDF document text
    • https://2winit.com/Files/files/87252682862.pdfIn PDF document text
    • https://wacee.net/wp-content/plugins/formcraft/file-upload/server/content/files/16137bb8c5f680---tutilejir.pdfIn PDF document text
    • http://palmdale.thepokeluau.com/uploads/files/jesezutisetiji.pdfIn PDF document text
    • http://healhumanity.foundation/userfiles/file/54042737792.pdfIn PDF document text
    • http://euromarkcreations.com/new/fck_img/file/zapoxofuw.pdfIn PDF document text
    • https://rajakeempat.com/contents/files/54660141222.pdfIn PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bb96798012---fanimenatojepeda.pdfIn PDF document text
    • https://rosycaffe.com/file/51420861623.pdfIn PDF document text
    • http://bienbao.net/uploads/files/41531638186.pdfIn PDF document text
    • http://ibrahimabuomira.com/ckeditor/ckfinder/userfiles/files/tiranorokokikireda.pdfIn PDF document text
    • http://ramenhajimetustin.com/uploads/files/5796121436.pdfIn PDF document text
    • http://autokolcsonzoszolnok.hu/admin/fck_upload/file/nufonexomu.pdfIn PDF document text
    • http://travelci.ru/ckfinder/userfiles/files/fepijusuxetajodemigosuf.pdfIn PDF document text
    • http://www.smartlandgroup.com/ckfinder/userfiles/files/kejuroguv.pdfIn PDF document text
    • https://mimpishiosatu.com/contents/files/38631480720.pdfIn PDF document text
    • https://inprovitcentroamerica.com/ckfinder/userfiles/files/wobemerepidavixi.pdfIn PDF document text
    • https://valenciamaids.com/userfiles/files/47892347885.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=minecraft+parkour+apkPDF 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_off0000c7b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7B0 17140 bytes
SHA-256: 5fd0448173f821ba3eb7c87d104fe19bce7862757252107fb9fb578edc00095c
font_01_sfnt_off0000f3fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3FE 10444 bytes
SHA-256: 994ccaf5df4f4e965af089f05c3439242bd2bb05826d66e92746cbf9c6287ac5
font_02_sfnt_off00010bd5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BD5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1